When providing two-way independent high-pressure high-flow oil sources, hydraulic system generally adopts two separate piston pumps or coaxial ones in series, causing complex structure and high cost. Therefore, single piston pump was proposed to achieve two-way high-pressure oil supply. Axial piston pump was designed with dual discharging inter-outer ring parallel allocation structure by changing cylinder structure, piston number, cap circuit and valve plate shape. Flow allocation structure was redesigned due to decreased single ring piston number, increased pressure shock and fluctuation in the chamber. Relief notch was cancelled in transition region from oil-discharging to oil-absorbing waist slots. After that, mismatch angle was increased to enlarge closed volume in chamber and reduce the pressure of unexhausted high-pressure oil in the interval between oil extraction and absorption. In transition region from oil-absorbing to oil-discharging waist slots, stepped flow area was used to replace original continuous flow area to weaken geometry requirements of relief notch. The optimized dual discharging flow allocation structure was conducted with theoretical analysis to establish dual discharging axial piston pump simulation model based on 45mL axial piston pump structure. There was small pressure shock in outer race by analyzing pressure shock and output flow in single piston chamber. Compared with traditional flow allocation structure, dual discharging oil output had smaller pressure fluctuation rate. Based on this, the designed dual discharging axial piston pump was piloted. The pilot dual discharging oil pump was compared with the original 45mL pump through pressure fluctuation, volumetric efficiency and noise tests. Result showed that the former had lower pressure fluctuation (decreased by 30%) and noise level, while its volumetric efficiency was not smaller than 92%. In general, the dual discharging axial piston pump can replace duplex pump to simplify system structure and reduce energy consumption. This new pump can also be used in closed circuit and differential cylinder hydraulic systems to make the system simpler and cost-effective.