The invention discloses a device for detecting the viscosity of an aldehyde-free adhesive for automotive trims. The device comprises a first fixing rack, a second fixing rack, a display screen and a connecting plate, wherein threaded holes are formed in the first fixing rack; the first fixing rack is connected with a buffer pad; the buffer pad is connected with the testing plate; threaded holes are formed in both the buffer pad and the testing plate; the display screen is positioned on a tension sensor; the tension sensor is arranged on the bottom surface of the connecting plate; the top surface of the connecting plate is connected with a first hydraulic rod; the first hydraulic rod is connected with a hydraulic cylinder through a second hydraulic rod; two limiting grooves are formed in the testing plate; the limiting grooves are symmetrically formed relative to the central line of the testing plate. The middle of the testing plate protrudes upwards, then testing can be implemented relatively easily, the area between the limiting grooves is the adhesion area of the adhesive, the identical adhesion areas are ensured for each time of testing, and thus the testing result accuracy is ensured.