diff --git a/independent-projects/qute/core/src/main/java/io/quarkus/qute/Parser.java b/independent-projects/qute/core/src/main/java/io/quarkus/qute/Parser.java
index b69b5e9100c7c..fa4461a393a56 100644
--- a/independent-projects/qute/core/src/main/java/io/quarkus/qute/Parser.java
+++ b/independent-projects/qute/core/src/main/java/io/quarkus/qute/Parser.java
@@ -477,9 +477,12 @@ private void flushTag() {
             // Parameter declaration
             // {@org.acme.Foo foo}
             Scope currentScope = scopeStack.peek();
-            int spaceIdx = content.indexOf(" ");
-            String key = content.substring(spaceIdx + 1, content.length());
-            String value = content.substring(1, spaceIdx);
+            String[] parts = content.substring(1).trim().split("[ ]{1,}");
+            if (parts.length != 2) {
+                throw parserError("invalid parameter declaration " + START_DELIMITER + buffer.toString() + END_DELIMITER);
+            }
+            String value = parts[0];
+            String key = parts[1];
             currentScope.putBinding(key, Expressions.typeInfoFrom(value));
             sectionStack.peek().currentBlock().addNode(new ParameterDeclarationNode(content, origin(0)));
         } else {
diff --git a/independent-projects/qute/core/src/test/java/io/quarkus/qute/ParserTest.java b/independent-projects/qute/core/src/test/java/io/quarkus/qute/ParserTest.java
index aba4d4f4e6357..1a12c2952f0c3 100644
--- a/independent-projects/qute/core/src/test/java/io/quarkus/qute/ParserTest.java
+++ b/independent-projects/qute/core/src/test/java/io/quarkus/qute/ParserTest.java
@@ -358,6 +358,20 @@ public void testInvalidBracket() {
                 "Parser error on line 1: invalid bracket notation expression in {foo.baz[}", 1);
     }
 
+    @Test
+    public void testInvalidParamDeclaration() {
+        assertParserError("{@com.foo }",
+                "Parser error on line 1: invalid parameter declaration {@com.foo }", 1);
+        assertParserError("{@ com.foo }",
+                "Parser error on line 1: invalid parameter declaration {@ com.foo }", 1);
+        assertParserError("{@com.foo.Bar bar baz}",
+                "Parser error on line 1: invalid parameter declaration {@com.foo.Bar bar baz}", 1);
+        assertParserError("{@}",
+                "Parser error on line 1: invalid parameter declaration {@}", 1);
+        assertParserError("{@\n}",
+                "Parser error on line 1: invalid parameter declaration {@\n}", 1);
+    }
+
     public static class Foo {
 
         public List<Item> getItems() {