The invention provides a device and a method for testing the adsorption rate of cement for emulsified asphalt. The device comprises the following components: a sample bin, a compensation bin, a circulating device, a recovery tank and a constant temperature device. According to the principle that the cement adsorbing the emulsified asphalt cannot pass through an adsorption sieve due to enlarged particle volume, the method is utilized for calculating the adsorption rate by measuring change in sample quality before and after adsorption. Through the adoption of the device and the method provided by the invention, the defects in the prior art can be overcome, and the adsorption rate of the cement for the emulsified asphalt can be tested under a constant temperature condition.