Provided is a washing method of a roller washing machine. The washing method comprises the steps of 1), washing; 2), rinsing; 3), turning on a draining pump, detecting whether or not the water level is lower than H1, if yes, executing the next step, otherwise executing step 3) again; 4), keeping the rotating speed at V1 for T1; 5), judging whether or not the load distribution is uniform, if yes, conducing pre-dewatering, otherwise executing step 4); 6), finishing pre-dewatering; 7), keeping the rotating speed at V1 for T1; 8), judging whether or not the load distribution is uniform, if yes, executing the next step, otherwise executing step 7); 9), keeping the rotating speed at V2 for T2, and then reaching V3; 10), detecting whether or not the water level is lower than H1, if yes, turning off the draining pump, otherwise executing step 9); 11), turning on an inlet valve; 12), judging whether or not the total water inlet time is greater than T4, if yes, executing step 15), otherwise executing the next step; 13), detecting whether or not the water level is higher than H2, if yes, executing the next step, otherwise executing step 12); 14), judging whether or not T5 is finished, if yes,executing the next step, otherwise executing step 14) again; 15), turning off the inlet valve, judging whether or not the delayed turn-on time reaches T6, if yes, turning on the draining pump, otherwise executing step 15) again; 16), judging whether or not the time of duration reaches T3, if yes, executing the next step, otherwise executing step 16) again; 17), judging whether or not the rinsingis the last time of rinsing, if yes, executing the next step, otherwise executing step 2); 18), completing the washing. The washing method can achieve double washing and save energy and has high efficiency, a high-speed washing water ring is formed, the decontamination and cleaning ability is stronger, and secondary pollution is avoided.