The invention relates to a high-stability aerial work platform driving chassis which comprises a chassis body, a driving device, a pit protection mechanism and a support leg structure. The driving device comprises a left steering wheel, a right steering wheel, a left wheel frame, a right wheel frame, a linkage frame, a steering cylinder and a steering bend plate; the pit protection mechanism comprises a left pit plate, a right pit plate, two first pit connecting plates, two second pit connecting plates, two third pit connecting plates, a fourth pit connecting plate, two movable seats, two guide shafts, two limit plates and two movable seat press springs; the support leg structure comprises a frame plate, a support leg plate, a support leg mounting plate, an outer support pipe, an inner support pipe and a support leg. By the above structure, the pit plates can rotate flexibly to meet requirements of different states, throughout performance is improved, steering angle limit can be increased, and use performance is enhanced.