--- a/src/ast_convert.rs
+++ b/src/ast_convert.rs
@@ -306,6 +306,7 @@ fn parse_expr(py: Python, ast: PyObject)
     let yield_from_type = ast_module.get(py, "YieldFrom").unwrap();
     let set_type = ast_module.get(py, "Set").unwrap();
     let setcomp_type = ast_module.get(py, "SetComp").unwrap();
+    let generatorexp_type = ast_module.get(py, "GeneratorExp").unwrap();
 
     assert!(is_instance(&ast, &ast_type));
 
@@ -435,6 +436,14 @@ fn parse_expr(py: Python, ast: PyObject)
         let generators = parse_list(py, generators, parse_comprehension);
 
         expr::SetComp(Box::new(elt), generators)
+    } else if is_instance(&ast, &generatorexp_type) {
+        let elt = ast.getattr(py, "elt").unwrap();
+        let generators = ast.getattr(py, "generators").unwrap();
+
+        let elt = parse_expr(py, elt);
+        let generators = parse_list(py, generators, parse_comprehension);
+
+        expr::GeneratorExp(Box::new(elt), generators)
     } else {
         println!("expr {}", ast);
         unreachable!()

--- a/src/ast_dump.rs
+++ b/src/ast_dump.rs
@@ -196,6 +196,7 @@ impl to_string_able for expr {
             expr::YieldFrom(value) => format!("yield from {}", value.to_string()),
             expr::Set(elts) => format!("{{{}}}", vec_to_strings_vec(elts).join(", ")),
             expr::SetComp(elt, generators) => format!("{{{} {}}}", elt.to_string(), vec_to_strings_vec(generators).join(" ")),
+            expr::GeneratorExp(elt, generators) => format!("({} {})", elt.to_string(), vec_to_strings_vec(generators).join(" ")),
         }
     }
 }

--- a/src/python_ast.rs
+++ b/src/python_ast.rs
@@ -88,7 +88,7 @@ pub enum expr {
     ListComp(Box<expr>, Vec<comprehension>),
     SetComp(Box<expr>, Vec<comprehension>),
     DictComp(Box<expr>, Box<expr>, Vec<comprehension>),
-    //GeneratorExp(Box<expr>, Vec<comprehension>)
+    GeneratorExp(Box<expr>, Vec<comprehension>),
 
     // the grammar constrains where yield expressions can occur
     Await(Box<expr>),

new file mode 100644
--- /dev/null
+++ b/tests/test_parse_files/test_generatorexp.py
@@ -0,0 +1,1 @@
+a = ((a, b) for a in range(5) for b in range(6))