The invention discloses an anti-derail traveling device of a small crawler-type chained deep-ploughing and excavating all-in-one machine. The anti-derail traveling device comprises a main beam. Supporting wheels are arranged on one side of the main beam. Rotating shafts of the supporting wheels are connected to the main beam. A front tensioning wheel and a rear tensioning wheel are arranged at the front end and the rear end of the supporting wheels correspondingly. A rotating shaft of the front tensioning wheel and a rotating shaft of the rear tensioning wheel are also connected to the main beam. A guide rail is located at the bottom of the supporting wheels and makes contact with the bottom of a rotating shaft between two wheel bodies of each supporting wheel. A tooth hole type crawler belt is engaged with a drive gear. According to the anti-derail traveling device of the small crawler-type chained deep-ploughing and excavating all-in-one machine, the guide rail is mounted in the midpoint of the bottom face of the supporting wheels, the possibility of deviation of the crawler traveling device is quite effectively lowered, the crawler traveling device can travel forwards along a straight line effectively, and the crawler belt is unlikely to derail even on bad road conditions. By adoption of the tooth hole type crawler belt, teeth on the drive gear are engaged with the tooth hole type crawler belt, the teeth at the upper end of the drive gear play a guiding role in the motion process of the tooth hole type crawler belt to enable the tooth hole type crawler belt to operate more stably, and the derailing risk of the crawler belt is further lowered.