A motor and a rotor thereof are provided. Taking the distance between the two endpoints of a permanent magnet of a motor rotor that are on the side away from the center of an iron core as the length L of the permanent magnet, and the distance between a line connecting the two endpoints of the permanent magnet that are on the side away from the center of the iron core and the center point on the side of the permanent magnet that is close to the centerline of the iron core as the width H of the permanent magnet, then H/L ≧ 1/10. By adjusting the relationship between the length L and width H of the permanent magnet, the air gap magnetic density of the permanent magnet can be effectively increased.