The present invention relates to a fully automatic fruit washing device with a washing brush. The fully automatic fruit washing device comprises a shell. A spray device, a washing mechanism and a waste liquid collection box are arranged in the shell successively from top to bottom. The washing mechanism consists of a first bracket, a second bracket, a rotating washing device, a washing brush device and a first rotating device. A sliding bracket is arranged between the first bracket and the second bracket, the washing brush device is arranged on the slide bracket, a rotary rail is arranged on the first bracket, two ends of the rotary washing device are connected to the first bracket via the rotary rail, the first rotary device is arranged at lower end of the rotary washing device, and the rotary washing device is connected to the shell via the first rotary device. The fully automatic fruit washing device with the washing brush is simple in structure and convenient in use, realizes an integration process of washing agent washing, clear water washing, and dewatering, effectively improves the fruit washing efficiency, and saves washing time.