The invention discloses a vertical travelling mechanism for a wind 
tower maintenance 
robot. The vertical travelling mechanism comprises a 
robot operation platform, an operation platform traction mechanism and a surface operation platform. The 
robot operation platform comprises a support, a robot 
actuator, the vertical travelling mechanism and a platform suction device; the operation platform traction mechanism comprises a fixing hanger, a telescopic 
cantilever and a 
servo lifting mechanism; the surface operation platform is disposed on a bearing platform of a wind generator or the ground near a wind 
tower, the surface operation platform comprises a 
robot control device and a working material conveying 
system, and the 
robot control device is in 
signal connection respectively with the robot 
actuator, a reel motor, a touch sensor, the platform suction device and a positioning suction device; the working material conveying 
system is connected with the robot 
actuator through a flexible conveying line. The vertical travelling mechanism has the advantages such as light weight, ease of implementation, low cost and no special requirement on operation sites and climbing faces.