diff --git a/transpiler/src/main/java/org/jsweet/transpiler/extension/Java2TypeScriptAdapter.java b/transpiler/src/main/java/org/jsweet/transpiler/extension/Java2TypeScriptAdapter.java
index 4faffc21..655af70f 100644
--- a/transpiler/src/main/java/org/jsweet/transpiler/extension/Java2TypeScriptAdapter.java
+++ b/transpiler/src/main/java/org/jsweet/transpiler/extension/Java2TypeScriptAdapter.java
@@ -72,6 +72,7 @@ import javax.lang.model.element.ElementKind;
 import javax.lang.model.element.ExecutableElement;
 import javax.lang.model.element.Modifier;
 import javax.lang.model.element.TypeElement;
+import javax.lang.model.type.PrimitiveType;
 import javax.lang.model.type.TypeKind;
 import javax.lang.model.type.TypeMirror;
 
@@ -1285,9 +1286,9 @@ public class Java2TypeScriptAdapter extends PrinterAdapter {
 				} else {
 					switch (targetMethodName) {
 					case "equals":
-                        if (types().isSameType(invocationElement.getTargetExpression().getType(),
-                                util().getType(String.class))
-                                || util().isNumber(invocationElement.getTargetExpression().getType())) {
+					    TypeMirror t1 = util().toPrimitiveTypeOrType(invocationElement.getTargetExpression().getType());
+                        TypeMirror t2 = util().toPrimitiveTypeOrType(invocationElement.getArgument(0).getType());
+                        if (types().isSameType(t1, t2) && util().isCoreType(t1)) {
                             if(isInlinedExpression(invocationElement)) {
                                 print("(");
                             }
diff --git a/transpiler/src/main/java/org/jsweet/transpiler/model/Util.java b/transpiler/src/main/java/org/jsweet/transpiler/model/Util.java
index 1409dbf6..8cea6ecb 100644
--- a/transpiler/src/main/java/org/jsweet/transpiler/model/Util.java
+++ b/transpiler/src/main/java/org/jsweet/transpiler/model/Util.java
@@ -56,6 +56,11 @@ public interface Util {
 	 */
 	boolean isNumber(TypeMirror type);
 
+    /**
+     * Tells if the given type is a boolean.
+     */
+    boolean isBoolean(TypeMirror type);
+
 	/**
 	 * Tells if the given element is deprecated.
 	 */
@@ -125,5 +130,13 @@ public interface Util {
      * @return a list of all the members
      */
     List<Element> getAllMembers(TypeElement typeElement);
-	
+
+    /**
+     * Gets the type as a primitive type (by unboxing it) when possible.
+     * 
+     * @param type the origin type
+     * @return the origin type or the corresponding primitive type if possible
+     */
+    TypeMirror toPrimitiveTypeOrType(TypeMirror type);
+    
 }
diff --git a/transpiler/src/main/java/org/jsweet/transpiler/model/support/UtilSupport.java b/transpiler/src/main/java/org/jsweet/transpiler/model/support/UtilSupport.java
index 7636502f..99b9d7d4 100644
--- a/transpiler/src/main/java/org/jsweet/transpiler/model/support/UtilSupport.java
+++ b/transpiler/src/main/java/org/jsweet/transpiler/model/support/UtilSupport.java
@@ -157,6 +157,11 @@ public class UtilSupport implements Util {
 		return org.jsweet.transpiler.util.Util.isNumber(type);
 	}
 
+    @Override
+    public boolean isBoolean(TypeMirror type) {
+        return org.jsweet.transpiler.util.Util.isBoolean(type);
+    }
+	
 	@Override
 	public boolean isDeprecated(Element element) {
 		return org.jsweet.transpiler.util.Util.isDeprecated(element);
@@ -231,4 +236,12 @@ public class UtilSupport implements Util {
         return getAllMembers((TypeElement)context.modelTypes.asElement(type));
     }
 	
+    @Override
+    public TypeMirror toPrimitiveTypeOrType(TypeMirror type) {
+        try {
+            return context.types.unboxedTypeOrType((Type)type);
+        } catch (Exception e) {
+            return type;
+        }
+    }
 }
diff --git a/transpiler/src/main/java/org/jsweet/transpiler/util/Util.java b/transpiler/src/main/java/org/jsweet/transpiler/util/Util.java
index 0165006e..1be46d5f 100644
--- a/transpiler/src/main/java/org/jsweet/transpiler/util/Util.java
+++ b/transpiler/src/main/java/org/jsweet/transpiler/util/Util.java
@@ -1059,6 +1059,21 @@ public class Util {
 		}
 	}
 
+    /**
+     * Returns true is the type is a boolean.
+     */
+    public static boolean isBoolean(TypeMirror type) {
+        if (type == null) {
+            return false;
+        }
+        switch (type.getKind()) {
+        case BOOLEAN:
+            return true;
+        default:
+            return false;
+        }
+    }
+	
 	/**
 	 * Returns true is the type is a core.
 	 */