The difficulty of the piano music "Mitsuha's Theme Song" is level 3-4.

It is a moderate challenge for students with certain piano foundation. The difficulty level of piano music is determined by the technical requirements, speed and musical complexity of the piece. The melody of "Mitsuha's Theme Song" is fresh and beautiful, and it is a good practice and performance piece for piano beginners. I am a piano beginner and want to try playing "Mitsuha's Theme". I will start practicing from the simple parts and gradually improve my skills and speed.