Abstract: To investigate the effects of venturi on the atomization,mixing and detonation process in pulse detonation engine(PDE), the Euler-Lagrange model for gas-droplets two phase detonation is built, while the gas and liquid equations are respectively calculated by the conservation element and solution element(CE/SE) method and fourth-order Runge-Kutta method. Numerical results show that the venturi can accelerate the liquid atomization, improve the gasoline-air distribution performance and shorten the deflagration to detonation transition (DDT) distance and time. When the injector is installed at the throat of venturi, PDE has the shortest DDT distance and time. The results can provide reference for the improvement of PDE.