With a large banana growing area in the tropics of China, about 35 million tons of waste straw will be produced each year, and the traditional way of dealing with banana straw is time consuming and polluting. Crushing banana straw back to the field is a green way of dealing with banana straw, and varieties of banana straw crushers have been developed in China. However, the diameter of banana straw in the mature stage can reach 250mm, banana straw crushing and return machine in the operation of uneven crushing, banana straw fiber entanglement serious, return machine operation quality and other problems still exist. In response to the problem that banana straw is not thoroughly crushed during the operation of banana straw crushing and returning to the field in tropical areas of China, and the straw block is entangled and blocked the key parts, which affects the normal operation of the machine, a double fixed knife slip-cutting type anti-tangle banana straw crushing and returning machine was designed. Based on the slip-cutting theorem, the dynamic slip-cutting angle during the rotation of the crushing knife with the shaft and the slip-cutting angle during the crushing process of the crushing fixed knife were analyzed, the L-shaped crushing fixed knife blade curve was designed according to the equal velocity spiral, and the structural parameters of the crushing knife were determined;the anti-winding plate was designed, the force analysis of the banana straw winding crushing knife roll was performed, and the number of anti-winding plate assembly and structural parameters were determined. The anti-winding plate was designed, the force on banana straw winding crushing knife roller was analyzed, the number of anti-winding plate assembly and structural parameters were determined;the anti-winding cover was used to improve the anti-winding performance at the knife roller connection;the device forward speed, crushing knife roller speed and anti-winding plate height were taken as test factors for banana straw crushing pass rate, throwing unevenness and the number of banana straw winding as three-level and three-factor orthogonal test, the establishment of factors and indicators of the response surface mathematical model was done, the relationship between factors and evaluation indicators was analyzed, and optimization of the influencing factors was carried out. The experiment results showed that the optimal combination of parameters for each test factor was as follows: the forward speed of the machine was 1.5m/s, the height of the anti-tangle plate was 41.6mm, and the speed of the crushing knife roller was 1800r/min, and then the banana straw crushing qualified rate was 93.8%, the number of banana straw winding was 26, and the unevenness of banana straw throwing was 12.1%. And the optimal combination of field test verification, with the optimization of the solution results of the error was small;the design of double fixed knife slide cut anti-tangle banana straw crushing machine whole machine anti-tangle performance was superior to satisfy the design requirements.