diff --git a/ext/bigdecimal/bigdecimal.c b/ext/bigdecimal/bigdecimal.c
index 99bd9f06..b414ff4e 100644
--- a/ext/bigdecimal/bigdecimal.c
+++ b/ext/bigdecimal/bigdecimal.c
@@ -2898,7 +2898,7 @@ rb_convert_to_BigDecimal(VALUE val, size_t digs, int raise_exception)
     else if (RB_TYPE_P(val, T_COMPLEX)) {
         VALUE im = rb_complex_imag(val);
         if (!is_zero(im)) {
-            /* TODO: handle raise_exception */
+            if (!raise_exception) return Qnil;
             rb_raise(rb_eArgError,
                      "Unable to make a BigDecimal from non-zero imaginary number");
         }
diff --git a/test/bigdecimal/test_bigdecimal.rb b/test/bigdecimal/test_bigdecimal.rb
index 4487f4a4..00992e3b 100644
--- a/test/bigdecimal/test_bigdecimal.rb
+++ b/test/bigdecimal/test_bigdecimal.rb
@@ -293,13 +293,12 @@ def test_BigDecimal_with_exception_keyword
     assert_nothing_raised(ArgumentError) {
       assert_equal(nil, BigDecimal(4.2, Float::DIG + 2, exception: false))
     }
-    # TODO: support conversion from complex
-    # assert_raise(RangeError) {
-    #   BigDecimal(1i, exception: true)
-    # }
-    # assert_nothing_raised(RangeError) {
-    #   assert_equal(nil, BigDecimal(1i, exception: false))
-    # }
+    assert_raise(ArgumentError) {
+      BigDecimal(1i, exception: true)
+    }
+    assert_nothing_raised(ArgumentError) {
+      assert_equal(nil, BigDecimal(1i, exception: false))
+    }
     assert_raise_with_message(TypeError, "can't convert nil into BigDecimal") {
       BigDecimal(nil, exception: true)
     }