The invention discloses a spacewalker which comprises a base. A first stand column and a second stand column are arranged at the upper end of the base. Armrests and two pedal swing arm assemblies arearranged between the first stand column and the second stand column. Each pedal swing arm assembly comprises a first-stage swing arm sleeving a fixed shaft. A shell is arranged at the bottom of each first-stage swing arm and provided with a telescopic lock. A second-stage swing arm is arranged at the lower end of each first-stage swing arm. A pedal is arranged at the bottom of each second-stage swing arm. Each first-stage swing arm is connected with the corresponding second-stage swing arm through an elastic part. Each second swing arm moves up and is fixed to the corresponding first-stage swing arm through a telescopic lock after the elastic part is compressed. By means of the spacewalker, legs can move back and forth and can also move stereoscopically, and the requirements of a trainee are met.