Background: Quantum dot lasers (QDLs) are promising semiconductor laser devices due to their discrete energy levels and strong carrier confinement, which enable high-speed operation and improved performance in applications such as optical communications, sensing, and quantum information processing. The interaction of these lasers with optical feedback significantly affects their dynamic behavior and stability. Objectives: This study aims to investigate the relaxation dynamics and stability characteristics of quantum dot lasers subjected to optical feedback by analyzing the influence of injection rate and detuning frequency on the system behavior. Methods: A theoretical analysis based on a rate-equation model describing the complex electric field, carrier density in the wetting layer, and occupation probability in quantum dots was employed. The steady-state conditions were obtained, and the Jacobian matrix was used to derive an analytical expression for the growth rate. Numerical simulations were then performed to evaluate the relaxation oscillation frequency and damping rate and to compare the dynamics of QDLs with and without optical feedback. Results: The results show that optical feedback increases the relaxation oscillation frequency and decreases the damping rate as the injection rate increases, leading to reduced system stability and the emergence of instability regions. For negative detuning frequency, bistability regions appear, enabling potential applications in optical switching and optical data storage. Conclusions: Optical feedback significantly influences the dynamical response of QDLs, modifying their stability and oscillatory behavior. These findings provide insights for controlling laser dynamics and improving the design of quantum dot laser systems for advanced photonic applications.