The utility model provides a gaseous telemetry unit based on absorb and imaging technique, gaseous telemetry unit is including assembling device, light source, first light filter filtering natural light with the light of gaseous absorptive wavelength awaits measuring for detection light central africa that the light source sent, the filtering of second light filter detect in the light sum natural light light corresponding to gas and interference gas 's the absorptive wavelength that awaits measuring, the process first light filter with assemble containing of device the await measuring light and the process of gaseous absorption information the second light filter forms images respectively with the light of assembling the device imaging device is last, the gaseous content that awaits measuring is learnt according to the light distribution of imaging device output to the analytical equipment. The utility model has the advantages of many gaseous spectrum appearance, with low costs that detect, need not to use.