diff --git a/include/ceres/numeric_diff_cost_function.h b/include/ceres/numeric_diff_cost_function.h
index 493412be1..c69f262f5 100644
--- a/include/ceres/numeric_diff_cost_function.h
+++ b/include/ceres/numeric_diff_cost_function.h
@@ -206,7 +206,6 @@ class NumericDiffCostFunction : public SizedCostFunction<kNumResiduals, Ns...> {
 
     using ParameterDims =
         typename SizedCostFunction<kNumResiduals, Ns...>::ParameterDims;
-    using Parameters = typename ParameterDims::Parameters;
 
     constexpr int kNumParameters = ParameterDims::kNumParameters;
     constexpr int kNumParameterBlocks = ParameterDims::kNumParameterBlocks;