Speed changing box and automobile

The invention discloses a speed changing box and an automobile. The speed changing box comprises a parallel-shaft-type speed changer and at least one planet gear speed changer connected with the output end of the parallel-shaft-type speed changer. Power is output after sequentially passing the parallel-shaft-type speed changer and the at least one planet gear speed changer. Each planet gear speed changer has two or more alternative different transmission ratios. When the parallel-shaft-type speed changer outputs in a definite gear, the different transmission ratios are switched through the planet gear speed changer, multiple different gears can be separated on the basis of the gear of the parallel-shaft-type speed changer, and accordingly the gear number is increased.