The utility model provides a power decentralized type rail -defect detector car, includes no. I car and no. II cars, connects through windscreen, coupling between no. I car and no. II cars, no. I car,no. II cars all include the automobile body, walk capable portion, power transmission system, braking system, electric system, and no. II cars are still including the system of detecting a flaw. Arranged between cab, spare parts in no. I car automobile body, soft parlor, bathroom, kitchen, arranged cab, meeting room, flaw detection room in no. II car automobile bodies, visited wheel maintenance room, coupling medium room. The utility model provides a car space is little, be short of power, move low quality, accurate scheduling problem is owed to the flaw detection. The power decentralized ison two sections cars, and two sections vehicle weight volumes, springs are that the matching is the same basically, are favorable to improving dynamic performance, reduces because the influence of vehicle stability subalternation factor to the detecting system that detects a flaw to improve the accuracy of flaw detection.