diff --git a/lib/dry/types/predicate_inferrer.rb b/lib/dry/types/predicate_inferrer.rb
index 0cc525a3..67ab976f 100644
--- a/lib/dry/types/predicate_inferrer.rb
+++ b/lib/dry/types/predicate_inferrer.rb
@@ -185,6 +185,11 @@ def visit_predicate(node)
           end
         end
 
+        # @api private
+        def visit_map(_node)
+          raise NotImplementedError, "map types are not supported yet"
+        end
+
         private
 
         # @api private
diff --git a/spec/dry/types/predicate_inferrer_spec.rb b/spec/dry/types/predicate_inferrer_spec.rb
index d2ffa86b..f024d6f4 100644
--- a/spec/dry/types/predicate_inferrer_spec.rb
+++ b/spec/dry/types/predicate_inferrer_spec.rb
@@ -188,4 +188,10 @@ def type(*args)
       expect(inferrer[custom_type]).to eql([type?: custom_type.primitive])
     end
   end
+
+  it "tells that map types are not supported" do
+    expect {
+      inferrer[type(:hash).map("integer", "string")]
+    }.to raise_error(NotImplementedError, /map types are not supported/)
+  end
 end