The invention discloses an organochlorine pesticide polluted site soil remediation pretreatment device and a method, and relates to the technical field of soil pollution treatment.The device comprises a soil turning device, a vehicle head, a carriage, a cab, a screening device, a conveying device, a high-temperature drying device, a plasma cracking reactor, a fungicide bin and a mixing bin; the soil turning device is rotatably installed at the front end of the vehicle head, the cab is fixedly installed above the vehicle head, and the carriage is fixedly installed behind the vehicle head. According to the device, a movable vehicle is taken as a carrier, soil containing organochlorine is treated. Compare with a conventional soil treatment method, according to the device, soil does not need to be transferred, the transportation cost is saved, the treatment cost of organochlorine pesticide soil is greatly reduced, and the device has a large popularization space.