The invention discloses an armrest mounting structure of an electrically propelled wheelchair. The armrest mounting structure is characterized by comprising armrest seats, a first armrest adjusting tube, a second armrest adjusting tube, a third armrest adjusting tube, a fourth armrest adjusting tube, a fifth armrest adjusting tube, a sixth armrest adjusting tube and a seventh armrest adjusting tube; the first armrest adjusting tube is arranged in the left-right direction, the second armrest adjusting tube and the third armrest adjusting tube are L-shaped, one end of the second armrest adjusting tube and one end of the third armrest adjusting tube are inserted to the left end and the right end of the first armrest adjusting tube respectively, the fourth armrest adjusting tube and the fifth armrest adjusting tube are arranged vertically, and one end of the fourth armrest adjusting tube and one end of the fifth armrest adjusting tube are inserted to the other end of the second armrest adjusting tube and the other end of the third armrest adjusting tube respectively. Through the structure, adjustment of armrests in the left-right direction and the height direction is achieved, and accordingly, requirements of users in different heights and shapes are met.