The high interface interconnection quality between the low temperature co-fired ceramic(LTCC)substrate and high silicon aluminum alloy carrier is required for the multichannel T/R module. In order to optimize the welding interface interconnection strength between the large-size LTCC substrate and the high silicon aluminum alloy carrier, the large area LTCC substrate and CE11 high silicon aluminum alloy carrier are designed by the experimental design method, and the welding test is carried out. The main effect method is adopted to identify that the key process factors influencing the welding interface interconnection strength are the cooling slope between the 183~140 ℃ and the welding peak temperature. The regression analysis method is used to establish the relational model between the above-mentioned two types of parameters and the interface wielding strength. The optimal welding process parameters combinations are 0.967 ℃/s for the cooling slope and 230 ℃ for the welding peak temperature by using the Adam algorithm based on the random gradient descent. Based on the optimized process parameters, the interface welding strength of the validated sample is 23.6 Pa, with a relative error of 2.1% from the predicted value of the optimized model, which proves that the study in this paper can predict and significantly improve the interface welding strength after brazing the large-size substrate and the high silicon aluminum alloy carrier.