Provided are a derailing prevention bogie based on side frame positioning detection and a derailing detection method therefor. The derailing prevention bogie comprises a shaft box positioning device (1), a side frame assembly (2), a swing bolster assembly (3), a fundamental braking device (4), a wheel shaft assembly (5), and a derailing detection device (6) mounted at an end part of the side frame assembly (2). The derailing detection device (6) comprises two pairs of supporting bases (7), two transverse beams (8) and two pairs of laser displacement measurers and processor systems (9). Through additionally providing the derailing detection device on the bogie, an early warning function before a railway vehicle is derailed is realized and the problem that the railway vehicle cannot predicate derailing is solved. Guarantees are provided for railway transportation safety and reduction of freight derailing accidents.