An equivalent circuit model for the design and analysis of two-section gain lever quantum dot (QD) laser is presented.This model is based on the three level rate equations with two independent carrier populations and a single longitudinal optical mode.By using the presented model,the effect of gain lever on QD laser performances is investigated.The results of simulation show that the main characteristics of laser such as threshold current,transient response,output power and modulation response are affected by differential gain ratios between the two-sections.