An improved SiC Lateral bipolar junction transistor(LBJT) model considering the recombination current at the SiC/SiO2 interface in the base region is introduced. The difference between the lateral silicon carbide bipolar junction transistor and its vertical structure is analyzed. The epitaxial layer and the semi-insulating mechanism of the lateral BJT are equivalent to the substrate capacitance. An additional diode parallel to the base junction of the SiC BJT is introduced to describe the composite current. The behavior model of SiC LBJT is established based on the SGP model of a vertical SiC BJT. The base transit time of the LBJT model is calibrated,and the switching characteristics of the model are close to those of the actual device. On comparison with the measured data, the accuracy error between the output characteristic curve of the improved model is found to be smaller than that of the comparison with LBJT model data that does not consider the recombination current. This model can accurately describe the behavior of LBJT devices affected by the recombination current.