diff --git a/flang/lib/Optimizer/Transforms/SimplifyIntrinsics.cpp b/flang/lib/Optimizer/Transforms/SimplifyIntrinsics.cpp
--- a/flang/lib/Optimizer/Transforms/SimplifyIntrinsics.cpp
+++ b/flang/lib/Optimizer/Transforms/SimplifyIntrinsics.cpp
@@ -1189,15 +1189,16 @@
 
   int maskRank;
   fir::KindTy kind = 0;
-  mlir::Type logicalConvertType = builder.getI1Type();
+  mlir::Type logicalElemType = builder.getI1Type();
   if (isOperandAbsent(mask)) {
     maskRank = -1;
   } else {
     maskRank = getDimCount(mask);
     mlir::Type maskElemTy = hlfir::getFortranElementType(maskDef.getType());
-    fir::LogicalType maskLogiTy = {maskElemTy.dyn_cast<fir::LogicalType>()};
-    kind = maskLogiTy.getFKind();
-    logicalConvertType = builder.getIntegerType(kind * 8);
+    fir::LogicalType logicalFirType = {maskElemTy.dyn_cast<fir::LogicalType>()};
+    kind = logicalFirType.getFKind();
+    // Convert fir::LogicalType to mlir::Type
+    logicalElemType = logicalFirType;
   }
 
   mlir::Operation *outputDef = args[0].getDefiningOp();
@@ -1221,11 +1222,11 @@
   auto typeGenerator = [rank](fir::FirOpBuilder &builder) {
     return genRuntimeMinlocType(builder, rank);
   };
-  auto bodyGenerator = [rank, maskRank, inputType, logicalConvertType,
+  auto bodyGenerator = [rank, maskRank, inputType, logicalElemType,
                         outType](fir::FirOpBuilder &builder,
                                  mlir::func::FuncOp &funcOp) {
     genRuntimeMinlocBody(builder, funcOp, rank, maskRank, inputType,
-                         logicalConvertType, outType);
+                         logicalElemType, outType);
   };
 
   mlir::func::FuncOp newFunc =
diff --git a/flang/test/Transforms/simplifyintrinsics.fir b/flang/test/Transforms/simplifyintrinsics.fir
--- a/flang/test/Transforms/simplifyintrinsics.fir
+++ b/flang/test/Transforms/simplifyintrinsics.fir
@@ -1767,16 +1767,16 @@
 // CHECK:           %[[FLAG_SET:.*]] = arith.constant 1 : i32
 // CHECK:           %[[FLAG_EMPTY:.*]] = arith.constant 0 : i32
 // CHECK:           fir.store %[[FLAG_EMPTY]] to %[[FLAG_ALLOC]] : !fir.ref<i32>
-// CHECK:           %[[BOX_MASK:.*]] = fir.convert %[[BOX_MASK_NONE]] : (!fir.box<none>) -> !fir.box<!fir.array<?xi32>>
+// CHECK:           %[[BOX_MASK:.*]] = fir.convert %[[BOX_MASK_NONE]] : (!fir.box<none>) -> !fir.box<!fir.array<?x!fir.logical<4>>>
 // CHECK:           %[[MAX:.*]] = arith.constant 2147483647 : i32
 // CHECK:           %[[CINDEX_1:.*]] = arith.constant 1 : index
 // CHECK:           %[[DIM_INDEX0:.*]] = arith.constant 0 : index
 // CHECK:           %[[DIMS:.*]]:3 = fir.box_dims %[[BOX_INARR]], %[[DIM_INDEX0]] : (!fir.box<!fir.array<?xi32>>, index) -> (index, index, index)
 // CHECK:           %[[EXTENT:.*]] = arith.subi %[[DIMS]]#1, %[[CINDEX_1]] : index
 // CHECK:           %[[DOLOOP:.*]] = fir.do_loop %[[ITER:.*]] = %[[CINDEX_0]] to %[[EXTENT]] step %[[CINDEX_1]] iter_args(%[[MIN:.*]] = %[[MAX]]) -> (i32) {
-// CHECK:             %[[MASK_ITEM:.*]] = fir.coordinate_of %[[BOX_MASK]], %[[ITER]] : (!fir.box<!fir.array<?xi32>>, index) -> !fir.ref<i32>
-// CHECK:             %[[MASK_ITEMVAL:.*]] = fir.load %[[MASK_ITEM]] : !fir.ref<i32>
-// CHECK:             %[[MASK_IF_ITEM:.*]] = fir.convert %[[MASK_ITEMVAL]] : (i32) -> i1
+// CHECK:             %[[MASK_ITEM:.*]] = fir.coordinate_of %[[BOX_MASK]], %[[ITER]] : (!fir.box<!fir.array<?x!fir.logical<4>>>, index) -> !fir.ref<!fir.logical<4>>
+// CHECK:             %[[MASK_ITEMVAL:.*]] = fir.load %[[MASK_ITEM]] : !fir.ref<!fir.logical<4>>
+// CHECK:             %[[MASK_IF_ITEM:.*]] = fir.convert %[[MASK_ITEMVAL]] : (!fir.logical<4>) -> i1
 // CHECK:             %[[IF_MASK:.*]] = fir.if %[[MASK_IF_ITEM]] -> (i32) {
 // CHECK:               fir.store %[[FLAG_SET]] to %[[FLAG_ALLOC]] : !fir.ref<i32>
 // CHECK:               %[[INARR_ITEM:.*]] = fir.coordinate_of %[[BOX_INARR]], %[[ITER]] : (!fir.box<!fir.array<?xi32>>, index) -> !fir.ref<i32>