As for electrical capacitance tomography ECT(Electrical Capacitance Tomography) system is the”soft field" effect and pathological characteristics and less qualitative effects，based on the principle of electrical ca-pacitance tomography imaging principle and imaging algorithm，proposes an image fusion method that based on thelocal variance for electrical capacitance tomography system. This method takes the linear back projection algorithm，conjugate gradient algorithm and the trust region algorithm all becoming foundation of image reconstruction. Because of complementary characteristics of each image，the reconstructed images after wavelet decomposition of thehigh frequency component and low frequency component respectively using local variance and weighted average fulion rule fusion. Finally，by using the inverse wavelet transforms to obtain a new image reconstruction. The simulation experiment results show that the accuracy of image fusion after improved，the error becomes small，the image iscloser to the prototype，provides a new method for the research of ECT image reconstruction.