The utility model relates to a particulate matter concentration detection equipment, include: lead to hole area for the externally is received and is treated tracer gas, treat that tracer gas contains at least a particulate matter, the light source for produce light and shine lead to hole area, light by lead to and to treat the tracer gas scattering among the hole area, at least one optical detector arranges and is following lead to in the direction of advance of the light of hole area scattering for detect the intensity of scattered light, the optics trap includes: incident light guidance assembly is used for the guide the light struck that the light source produced arrives lead to the part outside the hole area, make it no longer to shine lead to hole area, and scattered light guidance assembly, be used for the guide to follow the light struck that leads to the hole area scattering arrives part outside at least one optical detector, making it not, reecho arrives at least one optical detector. According to the utility model discloses a particulate matter concentration detection equipment's cost is lower and can detect particulate matter concentration with high precision.