The invention discloses a device for detecting haze particles base on solar-blind ultraviolet and a detection method thereof, and the device for detecting the haze particles comprises an LED (Light Emitting Diode) lamp used for emitting ultraviolet light, a spatial filter, a collimating lens, a polarizer, Lambada/4 wave plate, a molecular gas container and a photoelectric detector are arranged along the ultraviolet light propagation direction in sequence; the polarizer, the Lambada/4 wave plate are respectively connected with a stepper motor controller, and a computer is connected with the stepper motor controller. The invention also discloses a detection method for the haze particles by utilizing the device, the method comprises the steps of measuring the instrument matrix A of the photoelectric detector firstly; utilizing the measured instrument matrix A to obtain the Stokes vector matrix Sout of scattered light secondly after polarized ultraviolet light irradiates the haze particles to be detected; obtaining the diameters of the haze particles to be detected according to the mie scattering theory finally. The device for detecting the haze particles based on the solar-blind ultraviolet and the detection method thereof can overcome the limitation of a cassette measurement space, are not affected by the environment humidity and temperature, and are not affected by intereference of background light; all-weather open measurement to haze can be realized, meanwhile, the equipment cost is reduced, and is suitable for the industrial manufacture.