diff --git a/solidity_parser/parser.py b/solidity_parser/parser.py
index 30ea087..ea27b61 100644
--- a/solidity_parser/parser.py
+++ b/solidity_parser/parser.py
@@ -639,7 +639,7 @@ def visitPrimaryExpression(self, ctx):
         if ctx.BooleanLiteral():
             return Node(ctx=ctx,
                         type='BooleanLiteral',
-                        value=ctx.BooleanLiteral().getText() == 'True')
+                        value=ctx.BooleanLiteral().getText() == 'true')
 
         if ctx.HexLiteral():
             return Node(ctx=ctx,