The invention belongs to the technical field of safety in coal mines and relates to a coal rock adsorption deformation and porosity synchronous measurement device and a coal rock adsorption deformation and porosity synchronous measurement method. A strain sensor and a first solidified gas pressure sensor at the upper end of an adsorption tank are connected onto a multipath signal conditioner through a wire, a gas reducing valve and a second solidified gas pressure sensor are fixedly installed on a high pressure gas cylinder, the second solidified gas pressure sensor is connected onto the multipath signal conditioner through a wire, a pipeline on the high pressure gas cylinder is connected with a standard cylinder, a second mass flowmeter is installed on the pipeline, a rotating platform is installed below the adsorption tank, an X-ray source and a ray detector that are right opposite to the adsorption tank are fixedly installed in a constant temperature air bath installed outside the adsorption tank, a data acquisition and analysis system is installed on the ray detector, a first mass flowmeter and a vacuum degassing pump are connected onto a pipeline on the adsorption tank, a degassing control valve and a vacuum thermocouple meter are fixedly installed on the vacuum degassing pump, and the problem that the adsorption deformation and the porosity of a coal sample cannot be measured synchronously in the process of measurement of the adsorbed gas flow of the coal rock is solved.