diff --git a/hgext/beautifygraph.py b/hgext/beautifygraph.py
--- a/hgext/beautifygraph.py
+++ b/hgext/beautifygraph.py
@@ -9,6 +9,24 @@
 '''beautify log -G output by using Unicode characters (EXPERIMENTAL)
 
    A terminal with UTF-8 support and monospace narrow text are required.
+
+   The character substitutions used in the graph can be customized with
+   variables in the [beautifygraph] section::
+
+        /   ``beautifygraph.edge.diagonal1``
+        \   ``beautifygraph.edge.diagonal2``
+        -   ``beautifygraph.edge.horizontal``
+        |   ``beautifygraph.edge.vertical``
+        :   ``beautifygraph.edge.verticaldotted``
+       -+-  ``beautifygraph.edge.cross``
+       -+   ``beautifygraph.edge.verticalleft``
+        +-  ``beautifygraph.edge.verticalright``
+        ~   ``beautifygraph.edge.verticalstop``
+        _   ``beautifygraph.node.closesbranch``
+        @   ``beautifygraph.node.current``
+        x   ``beautifygraph.node.obsolete``
+        o   ``beautifygraph.node.other``
+        *   ``beautifygraph.node.unstable``
 '''
 
 from __future__ import absolute_import
@@ -19,6 +37,7 @@
     extensions,
     graphmod,
     pycompat,
+    registrar,
     templatekw,
 )
 
@@ -28,53 +47,69 @@
 # leave the attribute unspecified.
 testedwith = 'ships-with-hg-core'
 
-def prettyedge(before, edge, after):
-    if edge == '~':
-        return '\xE2\x95\xA7' # U+2567 ╧
-    if edge == '/':
-        return '\xE2\x95\xB1' # U+2571 ╱
-    if edge == '-':
-        return '\xE2\x94\x80' # U+2500 ─
-    if edge == '|':
-        return '\xE2\x94\x82' # U+2502 │
-    if edge == ':':
-        return '\xE2\x94\x86' # U+2506 ┆
-    if edge == '\\':
-        return '\xE2\x95\xB2' # U+2572 ╲
+configtable = {}
+configitem = registrar.configitem(configtable)
+
+configitem('beautifygraph', 'edge.verticalstop',   '\xE2\x95\xA7')  # U+2567 ╧
+configitem('beautifygraph', 'edge.diagonalcross',  '\xE2\x95\xB3')  # U+2573 ╳
+configitem('beautifygraph', 'edge.diagonal1',      '\xE2\x95\xB1')  # U+2571 ╱
+configitem('beautifygraph', 'edge.horizontal',     '\xE2\x94\x80')  # U+2500 ─
+configitem('beautifygraph', 'edge.vertical',       '\xE2\x94\x82')  # U+2502 │
+configitem('beautifygraph', 'edge.verticaldotted', '\xE2\x94\x86')  # U+2506 ┆
+configitem('beautifygraph', 'edge.diagonal2',      '\xE2\x95\xB2')  # U+2572 ╲
+configitem('beautifygraph', 'edge.verticalright',  '\xE2\x94\x9C')  # U+251C ├
+configitem('beautifygraph', 'edge.verticalleft',   '\xE2\x94\xA4')  # U+2524 ┤
+configitem('beautifygraph', 'edge.cross',          '\xE2\x94\xBC')  # U+253C ┼
+configitem('beautifygraph', 'node.other',          '\xE2\x97\x8B')  # U+25CB ○
+configitem('beautifygraph', 'node.current',        '\xE2\x97\x8D')  # U+25CD ◍
+configitem('beautifygraph', 'node.unstable',       '\xE2\x88\x97')  # U+2217 ∗
+configitem('beautifygraph', 'node.obsolete',       '\xE2\x97\x8C')  # U+25CC ◌
+configitem('beautifygraph', 'node.closesbranch',   '\xE2\x95\xA4')  # U+2564 ╤
+
+def getsubstitutions(ui):
+    return {
+      '~':  ui.config('beautifygraph', 'edge.verticalstop'),
+      '/':  ui.config('beautifygraph', 'edge.diagonal1'),
+      '-':  ui.config('beautifygraph', 'edge.horizontal'),
+      '|':  ui.config('beautifygraph', 'edge.vertical'),
+      ':':  ui.config('beautifygraph', 'edge.verticaldotted'),
+      '\\': ui.config('beautifygraph', 'edge.diagonal2'),
+      '+-': ui.config('beautifygraph', 'edge.verticalright'),
+      '-+': ui.config('beautifygraph', 'edge.verticalleft'),
+      '+':  ui.config('beautifygraph', 'edge.cross'),
+      'o':  ui.config('beautifygraph', 'node.other'),
+      '@':  ui.config('beautifygraph', 'node.current'),
+      '*':  ui.config('beautifygraph', 'node.unstable'),
+      'x':  ui.config('beautifygraph', 'node.obsolete'),
+      '_':  ui.config('beautifygraph', 'node.closesbranch'),
+    }
+
+def prettyedge(substitutions, before, edge, after):
     if edge == '+':
         if before == ' ' and not after  == ' ':
-            return '\xE2\x94\x9C' # U+251C ├
+            return substitutions.get('+-', edge)
         if after  == ' ' and not before == ' ':
-            return '\xE2\x94\xA4' # U+2524 ┤
-        return '\xE2\x94\xBC' # U+253C ┼
-    return edge
+            return substitutions.get('-+', edge)
+    return substitutions.get(edge, edge)
 
-def convertedges(line):
+def convertedges(substitutions, line):
     line = ' %s ' % line
     pretty = []
     for idx in pycompat.xrange(len(line) - 2):
-        pretty.append(prettyedge(line[idx:idx + 1],
+        pretty.append(prettyedge(substitutions,
+                                 line[idx:idx + 1],
                                  line[idx + 1:idx + 2],
                                  line[idx + 2:idx + 3]))
     return ''.join(pretty)
 
-def getprettygraphnode(orig, *args, **kwargs):
-    node = orig(*args, **kwargs)
-    if node == 'o':
-        return '\xE2\x97\x8B' # U+25CB ○
-    if node == '@':
-        return '\xE2\x97\x8D' # U+25CD ◍
-    if node == '*':
-        return '\xE2\x88\x97' # U+2217 ∗
-    if node == 'x':
-        return '\xE2\x97\x8C' # U+25CC ◌
-    if node == '_':
-        return '\xE2\x95\xA4' # U+2564 ╤
-    return node
+def getprettygraphnode(orig, repo, *args, **kwargs):
+    node = orig(repo, *args, **kwargs)
+    return getsubstitutions(repo.ui).get(node, node)
 
 def outputprettygraph(orig, ui, graph, *args, **kwargs):
+    substitutions = getsubstitutions(ui)
     (edges, text) = zip(*graph)
-    graph = zip([convertedges(e) for e in edges], text)
+    graph = zip([convertedges(substitutions, e) for e in edges], text)
     return orig(ui, graph, *args, **kwargs)
 
 def extsetup(ui):
diff --git a/tests/test-glog-beautifygraph.t b/tests/test-glog-beautifygraph.t
--- a/tests/test-glog-beautifygraph.t
+++ b/tests/test-glog-beautifygraph.t
@@ -1,3 +1,29 @@
+  $ hg help beautifygraph
+  beautifygraph extension - beautify log -G output by using Unicode characters
+  (EXPERIMENTAL)
+  
+     A terminal with UTF-8 support and monospace narrow text are required.
+  
+     The character substitutions used in the graph can be customized with
+     variables in the [beautifygraph] section:
+  
+        /   ``beautifygraph.edge.diagonal1``
+        \   ``beautifygraph.edge.diagonal2``
+        -   ``beautifygraph.edge.horizontal``
+        |   ``beautifygraph.edge.vertical``
+        :   ``beautifygraph.edge.verticaldotted``
+       -+-  ``beautifygraph.edge.cross``
+       -+   ``beautifygraph.edge.verticalleft``
+        +-  ``beautifygraph.edge.verticalright``
+        ~   ``beautifygraph.edge.verticalstop``
+        _   ``beautifygraph.node.closesbranch``
+        @   ``beautifygraph.node.current``
+        x   ``beautifygraph.node.obsolete``
+        o   ``beautifygraph.node.other``
+        *   ``beautifygraph.node.unstable``
+  
+  (use 'hg help extensions' for information on enabling extensions)
+
 @  (34) head
 |
 | o  (33) head
@@ -3112,3 +3138,84 @@
   
 
   $ cd ..
+
+Construct a magical repo whose ascii graph log contains all the possible symbols.
+
+  $ hg init configuration
+  $ cd configuration
+
+  $ touch file0
+  $ hg commit -Aqm revision0
+  $ touch file1
+  $ hg commit -Aqm revision1
+  $ touch file2
+  $ hg commit -Aqm revision2
+  $ touch file3
+  $ hg commit -Aqm revision3
+  $ hg update -q null
+  $ touch file4
+  $ hg commit -Aqm revision4
+  $ hg update -q 3
+  $ hg merge -q 4
+  $ touch file5
+  $ hg commit -Aqm revision5
+  $ hg update -q null
+  $ touch file6
+  $ hg branch -q foo
+  $ hg commit -Aqm revision6
+  $ hg merge -q 3
+  $ touch file7
+  $ hg commit -Aqm revision7 --close-branch
+  $ hg update -q 4
+  $ hg merge -q 3
+  $ touch file8
+  $ hg commit -Aqm revision8
+  $ hg update -q 6
+  $ hg merge -q 5
+  $ touch file9
+  $ hg commit -Aqm revision9
+  $ touch file10
+  $ hg commit -Aqm revision10
+  $ hg debugobsolete `hg log -r 9 -T '{node}'`
+  obsoleted 1 changesets
+  1 new orphan changesets
+  $ hg update -q 8
+
+All symbols should be configurable.
+
+  $ hg log -G -q -r '(1:)-2' \
+  > --config beautifygraph.edge.diagonal1=a \
+  > --config beautifygraph.edge.diagonal2=b \
+  > --config beautifygraph.edge.cross=c \
+  > --config beautifygraph.edge.horizontal=d \
+  > --config beautifygraph.edge.vertical=e \
+  > --config beautifygraph.edge.verticaldotted=f \
+  > --config beautifygraph.edge.verticalleft=g \
+  > --config beautifygraph.edge.verticalright=h \
+  > --config beautifygraph.edge.verticalstop=i \
+  > --config beautifygraph.node.closesbranch=j \
+  > --config beautifygraph.node.current=📎 \
+  > --config beautifygraph.node.obsolete=l \
+  > --config beautifygraph.node.other=m \
+  > --config beautifygraph.node.unstable=n
+  n  10:3bf4adf1e513
+  e
+  l    9:a4d281932d8a
+  eb
+  e e 📎  8:b9029cea3597 (esc)
+  e e eb
+  e hdcdddj  7:12cd82bb4409
+  e e e e
+  e m e e  6:11bb041c7deb
+  e  a a
+  mdddg  5:0b61ae539b30
+  ea a
+  e m  4:f2e786cf2f3d
+  e
+  m  3:561d8244024e
+  f
+  m  1:388ecb15405b
+  e
+  i
+
+  $ cd ..