In order to reduce the flow pulsation rate of the string rotor pump and increase the area utilization coefficient of the rotor,a double meshing string rotor pump with two pairs of rotors was proposed.The influence of the rotor pitch ratio on the pulsation rate of the rotor pump and the rotor area utilization factor was analyzed,the relationship between the flow pulsation rate of the double meshing rotor pump and the differential angle between the two pairs of rotors was investigated.It is concluded that when the differential angle 〖BF〗α=π/(2z)〖BFQ〗,the pulsation rate of the double meshing string rotor pump is 0;at this time,the rotor area ratio can be increased by increasing the rotor pitch ratio,so that the rotor area utilization factor is increased from 245% to 451%.The research results show that the double meshing string rotor pump has the characteristics of high rotor area utilization coefficient and no flow pulsation.