With the rapid development of science and technology and industry, the formation of haze has been accelerated. Haze seriously harms our living environment and people's physical and mental health. Among them, atmospheric particulate pollution is the most serious environmental pollution at present. Therefore, timely and effective measures should be taken to detect atmospheric particulates in the environment, and then prevention and treatment of haze can effectively improve the environmental quality. Therefore, this paper designs an improved device for particle concentration detection based on laser scattering and micro-amplification, which is based on the previous designed concentration detection device. This device takes Mie scattering as the theoretical basis. The light source is a semiconductor laser, and the scattered light generated by the light irradiation of particles is further analyzed to obtain the particle property information after amplification by the microscopic equipment. At the same time, the photoelectric sensor absorbs the scattered light, and finally the particle mass concentration is reflected by pulse signal and optical signal together. There are two improvements in this device: 1. The structure of the stray light absorption part is modified to make more accurate measurement of experimental results and reduce the influence of stray light on the whole experiment; 2. Combined with image processing, the morphological features of particles can be acquired more accurately.