<p>The present study provides a comparative modeling and simulation analysis of two- and three-level quantum dot (QD) laser systems based on rate equations. The dynamic behavior of carrier densities in the wetting layer (WL) and QD states, along with the rise photon density evolution in the optical cavity, is investigated under varying injection currents. In the two-level model, carriers are captured from the WL directly into the ground state (GS), whereas in the three-level model, carriers first occupy an intermediate excited state (ES) before transitioning to the GS. Time-dependent rate equations are formulated to describe the occupation probability and photon dynamics in both systems. MATLAB simulations demonstrate how capture, relaxation, and recombination lifetimes affect carrier accumulation and changes in the gain integral. The results reveal notable differences in dynamic response and photon buildup between the two models, highlighting the crucial role of intermediate state dynamics in QD laser performance.</p>