The utility model discloses a photoacoustic CO2 sensor easy to assemble, which relates to the technical field of sensors and comprises a photosensor, an
acoustic sensor and a
carbon dioxide sensor, a first clamping component is fixed on one side of the photosensor, a first pin plate is fixed on one side of the
acoustic sensor, and a second clamping component is fixed on the other side of the
acoustic sensor. A second pin plate is fixed to one side of the
carbon dioxide sensor, the first clamping
assembly comprises two transverse plates and two vertical plates, two movable plates are in sliding fit between the two vertical plates, two lower pressing plates are in sliding fit between the two transverse plates, two
extrusion plates are fixed to one sides of the lower pressing plates, clamping plates are fixed to one sides of the movable plates, and clamping grooves are formed in the two side faces of the first pin plate. Through clamping cooperation between the first clamping
assembly and the first pin plate, between the second clamping
assembly and the second pin plate, and between the first clamping assembly and the second pin plate, free combination, assembly and fixation of the optical sensor, the acoustic sensor and the
carbon dioxide sensor can be realized, so as to meet
information acquisition requirements in different use environments.