An electric wheelchair comprising a movable seat part (1), a body part (2) served as a support for the seat part, a seat adjustment mechanism (3) arranged under the seat part, a bottom part (4), and a crawler moving mechanism (5). The crawler moving mechanism (5) comprises two sets of crawlers arranged respectively at both sides underneath the bottom part, and each of which comprises a front crawler and a rear crawler. The bottom part (4) is comprised of a front portion and a rear portion, which are movably connected with a coupling arrangement and capable of deflection with respect to each other. The crawler moving mechanism (5) further comprises movable stretching crawlers arranged respectively at outside of the front crawler, and fixed stair-climbing crawlers arranged respectively at outside of the rear crawler, wherein a free end of the fixed stair-climbing crawler forms a specific angle relative to the rear crawler.