diff --git a/omegaconf/grammar/OmegaConfGrammarLexer.g4 b/omegaconf/grammar/OmegaConfGrammarLexer.g4
index 30c9458fe..f7ab2044a 100644
--- a/omegaconf/grammar/OmegaConfGrammarLexer.g4
+++ b/omegaconf/grammar/OmegaConfGrammarLexer.g4
@@ -66,7 +66,7 @@ BOOL:
 NULL: [Nn][Uu][Ll][Ll];
 
 UNQUOTED_CHAR: [/\-\\+.$%*@?|];  // other characters allowed in unquoted strings
-ID: (CHAR|'_') (CHAR|DIGIT|'_')*;
+ID: (CHAR|'_') (CHAR|DIGIT|'_'|'-')*;
 ESC: (ESC_BACKSLASH | '\\(' | '\\)' | '\\[' | '\\]' | '\\{' | '\\}' |
       '\\:' | '\\=' | '\\,' | '\\ ' | '\\\t')+;
 WS: [ \t]+;
diff --git a/omegaconf/grammar_parser.py b/omegaconf/grammar_parser.py
index 85a931154..3c883c2cf 100644
--- a/omegaconf/grammar_parser.py
+++ b/omegaconf/grammar_parser.py
@@ -25,7 +25,7 @@
 _node_access = f"\\.{_key_maybe_brackets}"  # .foo, [foo], [$bar]
 _node_path = f"(\\.)*({_key_maybe_brackets})({_node_access})*"  # [foo].bar, .foo[bar]
 _node_inter = f"\\${{\\s*{_node_path}\\s*}}"  # node interpolation ${foo.bar}
-_id = "[a-zA-Z_]\\w*"  # foo, foo_bar, abc123
+_id = "[a-zA-Z_][\\w\\-]*"  # foo, foo_bar, foo-bar, abc123
 _resolver_name = f"({_id}(\\.{_id})*)?"  # foo, ns.bar3, ns_1.ns_2.b0z
 _arg = r"[a-zA-Z_0-9/\-\+.$%*@?|]+"  # string representing a resolver argument
 _args = f"{_arg}(\\s*,\\s*{_arg})*"  # list of resolver arguments
diff --git a/tests/test_grammar.py b/tests/test_grammar.py
index 830aec8d0..f4bfa0028 100644
--- a/tests/test_grammar.py
+++ b/tests/test_grammar.py
@@ -613,6 +613,7 @@ def visit() -> Any:
         "x ${ab.cd.ef.gh} y",
         "$ ${foo} ${bar} ${boz} $",
         "${foo:bar}",
+        "${foo-bar:bar-foo}",
         "${foo : bar, baz, boz}",
         "${foo:bar,0,a-b+c*d/$.%@?|}",
         r"\${foo}",