diff --git a/Libraries/LibWeb/CSS/Parser/Parser.h b/Libraries/LibWeb/CSS/Parser/Parser.h
index 2a1b5229d99..0fbf6ec8cd5 100644
--- a/Libraries/LibWeb/CSS/Parser/Parser.h
+++ b/Libraries/LibWeb/CSS/Parser/Parser.h
@@ -436,6 +436,8 @@ private:
     RefPtr<CSSStyleValue const> parse_grid_area_shorthand_value(TokenStream<ComponentValue>&);
     RefPtr<CSSStyleValue const> parse_grid_shorthand_value(TokenStream<ComponentValue>&);
 
+    RefPtr<CSSStyleValue const> parse_list_of_time_values(PropertyID, TokenStream<ComponentValue>&);
+
     RefPtr<CalculationNode const> convert_to_calculation_node(CalcParsing::Node const&, CalculationContext const&);
     RefPtr<CalculationNode const> parse_a_calculation(Vector<ComponentValue> const&, CalculationContext const&);
 
diff --git a/Libraries/LibWeb/CSS/Parser/PropertyParsing.cpp b/Libraries/LibWeb/CSS/Parser/PropertyParsing.cpp
index fc5cf49f778..328c0af1a60 100644
--- a/Libraries/LibWeb/CSS/Parser/PropertyParsing.cpp
+++ b/Libraries/LibWeb/CSS/Parser/PropertyParsing.cpp
@@ -670,6 +670,10 @@ Parser::ParseErrorOr<NonnullRefPtr<CSSStyleValue const>> Parser::parse_css_value
         if (auto parsed_value = parse_transition_value(tokens); parsed_value && !tokens.has_next_token())
             return parsed_value.release_nonnull();
         return ParseError::SyntaxError;
+    case PropertyID::TransitionDelay:
+        if (auto parsed_value = parse_list_of_time_values(property_id, tokens); parsed_value && !tokens.has_next_token())
+            return parsed_value.release_nonnull();
+        return ParseError::SyntaxError;
     case PropertyID::TransitionProperty:
         if (auto parsed_value = parse_transition_property_value(tokens); parsed_value && !tokens.has_next_token())
             return parsed_value.release_nonnull();
@@ -3783,6 +3787,26 @@ RefPtr<CSSStyleValue const> Parser::parse_transition_value(TokenStream<Component
     return TransitionStyleValue::create(move(transitions));
 }
 
+RefPtr<CSSStyleValue const> Parser::parse_list_of_time_values(PropertyID property_id, TokenStream<ComponentValue>& tokens)
+{
+    auto transaction = tokens.begin_transaction();
+    auto time_values = parse_a_comma_separated_list_of_component_values(tokens);
+    StyleValueVector time_value_list;
+    for (auto const& value : time_values) {
+        TokenStream time_value_tokens { value };
+        auto time_style_value = parse_time_value(time_value_tokens);
+        if (!time_style_value)
+            return nullptr;
+        if (time_value_tokens.has_next_token())
+            return nullptr;
+        if (!time_style_value->is_calculated() && !property_accepts_time(property_id, time_style_value->as_time().time()))
+            return nullptr;
+        time_value_list.append(*time_style_value);
+    }
+
+    transaction.commit();
+    return StyleValueList::create(move(time_value_list), StyleValueList::Separator::Comma);
+}
 RefPtr<CSSStyleValue const> Parser::parse_transition_property_value(TokenStream<ComponentValue>& tokens)
 {
     // https://drafts.csswg.org/css-transitions/#transition-property-property
diff --git a/Tests/LibWeb/Text/expected/wpt-import/css/css-transitions/parsing/transition-delay-valid.txt b/Tests/LibWeb/Text/expected/wpt-import/css/css-transitions/parsing/transition-delay-valid.txt
new file mode 100644
index 00000000000..4acdaf390de
--- /dev/null
+++ b/Tests/LibWeb/Text/expected/wpt-import/css/css-transitions/parsing/transition-delay-valid.txt
@@ -0,0 +1,9 @@
+Harness status: OK
+
+Found 4 tests
+
+4 Pass
+Pass	e.style['transition-delay'] = "0s" should set the property value
+Pass	e.style['transition-delay'] = "500ms" should set the property value
+Pass	e.style['transition-delay'] = "1s, 2s" should set the property value
+Pass	e.style['transition-delay'] = "-1s, -2s" should set the property value
\ No newline at end of file
diff --git a/Tests/LibWeb/Text/input/wpt-import/css/css-transitions/parsing/transition-delay-valid.html b/Tests/LibWeb/Text/input/wpt-import/css/css-transitions/parsing/transition-delay-valid.html
new file mode 100644
index 00000000000..72a40b8ffd0
--- /dev/null
+++ b/Tests/LibWeb/Text/input/wpt-import/css/css-transitions/parsing/transition-delay-valid.html
@@ -0,0 +1,20 @@
+<!DOCTYPE html>
+<html>
+<head>
+<meta charset="utf-8">
+<title>CSS Transitions: parsing transition-delay with valid values</title>
+<link rel="help" href="https://drafts.csswg.org/css-transitions/#propdef-transition-delay">
+<meta name="assert" content="transition-delay supports the full grammar '<time> #'.">
+<script src="../../../resources/testharness.js"></script>
+<script src="../../../resources/testharnessreport.js"></script>
+<script src="../../../css/support/parsing-testcommon.js"></script>
+</head>
+<body>
+<script>
+test_valid_value("transition-delay", '0s');
+test_valid_value("transition-delay", '500ms');
+test_valid_value("transition-delay", '1s, 2s');
+test_valid_value("transition-delay", '-1s, -2s');
+</script>
+</body>
+</html>