We have constructed a new pressure-velocity coupling method, named SIMPLERS (SIMPLER-Strict), based on SIMPLER (SIMPLE-Revised). In SIMPLER, unlike in SIMPLE, the pressure is calculated directly, and velocity is estimated from the calculated pressure field. In addition, to estimate the pressure field, velocity is simultaneously estimated considering the effect of neighboring points, and in SIMPLERS the pressure correction equation is solved to enable the velocity correction to be used. This treatment is expected to improve the convergence rate of the calculation. To validate this method, we apply SIMPLERS to back step flow (a flow case that is often used as a benchmark test) and the combustion field, and compare the convergence rate with those of SIMPLE and SIMPLER.