The time delay characteristics of integrated waveguide microring resonator with tunable coupler constructed by the Mach-Zehnder interferometer (MZI) is analyzed,and the time delay response function is deduced. The results show that the variation of the phase difference between the two arms of MZI tunes the equivalent coupling coefficient of the microring resonator,and it also changes the additional phase of the tunable coupler,which makes the resonant frequency shift of the microring resonator. The influence of the discrepancy of coupling coefficients of the 3 dB couplers in MZI on the tuning range of the equivalent coupling coefficient and the resonant frequency shift of the microring resonator is also presented. By amending the phase of ring waveguide,the target delay time of 0.6 ns,bandwith of 2 GHz,and delay time ripple metric less than 1×10-3 ns2 are obtained with cascaded four microring resonators.