The invention discloses a double-row easy-to-play thumb piano, and the musical instrument comprises a piano key group A and a piano key group B which are arranged back to back; each of the piano key group A and the piano key group B is provided with nine piano keys, the nine piano keys are distributed in a staggered manner and are different in length, and the musical scale arrangement sequence of the piano keys of the piano key group A1 from left to right is D4, A4, B3, F4, G3, E4, A3, G4 and C4 in the international acoustics pitch recording method; the alto 2, the alto 6, the bass 7, the alto 4, the bass 5, the alto 3, the bass 6, the alto 5 and the alto 1 in the pitch mark of the C-tone numbered musical notation. Two rows of musical scales are distributed to form a high and low pitch staggered distribution structure, so that sound finding is facilitated during finger operation, sound mixing is avoided, back-to-back arrangement and mutual interference are avoided, two persons can be operated and used simultaneously, the use pleasure is increased, and meanwhile, the sound harmonizing effect is good.