To provide theoretical support for modeling and designing perovskite quantum dot devices pumped by electron beams, this paper explores the microscopic luminescence process of perovskite quantum dot films pumped by electron beams, which reveals the energy conversion model and luminescence mechanism. Firstly, the paper analyzes the microscopic luminescence and lasing processes of perovskite quantum dots pumped by electron beams theoretically. Furthermore, the lasing and luminescence thresholds of quantum dots pumped by electron beams are found to be the macroscopic physical constraint boundaries that should be detected to build the energy conversion model. Then, the effective detection methods of lasing and luminescence thresholds are analyzed and discussed, and specific evaluation experiments have been carried out repeatedly. Finally, the relationship among luminescence energy conversion efficiency, polarization distribution of nanocrystals, and electron beam pumping intensity in perovskite quantum dot films is simulated and constructed by combining with the detection of physical constraint boundaries.