The invention discloses an automatic unmanned intelligent roadbed deformation parameter acquisition system and a signal processing method. A vehicle in-place perceiving module is connected with a main controller, multiple roadbed deformation test sensors are connected with the main controller through an acquisition board, when a front trigger sensor has no signal output, the main controller is in a standby state, the acquisition board is in a power off state, and the whole system is in a low power consumption mode; when the vehicle in-place perceiving module outputs a signal, a power source circuit is controlled by the main controller to supply power for the acquisition board, and the whole system enters a work state. An actually-measured roadbed deformation signal contains interference components, and the least square method is utilized to eliminate a strain signal datum line zero line deviation problem; secondly, a wavelet signal interference elimination method is further utilized, noise influence is eliminated, and a signal to noise ratio is improved; lastly, a derivation method is proposed to carry out derivation of a signal after processing to acquire the peak point time, and an interval parameter between signal peaks is extracted.