The invention discloses an anti-overflow device at a roller water injection port and a roller washing machine. The anti-overflow device comprises a water flow baffle, the water flow baffle extends along an outer tube to an inner tube and is installed at the water injection port, and water flow is blocked to run back into the water injection port along with the inner tube at a high speed. The anti-overflow device further comprises a blocking rib, and the blocking rib is arranged on the inner side of the water injection port and close to the outer tube. The roller washing machine comprises the anti-overflow device at the roller water injection port. The principle of fluid mechanics is adopted in the anti-overflow device at the roller water injection port, the change of liquid flow in the roller is realized, and the anti-overflow effect is good; the anti-overflow device at the roller water injection port is simple in structure, and has a high reliability; the components are simple, and the economical efficiency is good.