When Imperial Prince Morihito (later to become Emperor Nijo) became Crown Prince in 1155, Nakatsuna was appointed to Kurodo (sovereign's secretary) and served Togu (the Prince).
久寿2年（1155年）守仁親王（後の二条天皇）が立太子されると蔵人に補され、東宮（皇太子）に仕えた。