The invention provides a quality detecting device and method for wheat seeds so as to solve the problem that quality detecting equipment for the wheat seeds in the prior art is not suitable for use bypeasants. The quality detecting device comprises a waste seed box for containing waste seeds, a screening unit obliquely arranged on the upper surface of the waste seed box to screen the seeds, a hopper for receiving the to-be-detected seeds falling from the screening unit, a seeding device arranged at the seed outlet end of the hopper, a seed outlet pipe which is arranged at the output end of the seeding device and only allows single seeds to pass, a seed storage box arranged at the seed outlet end of the seed outlet pipe as well as a control component comprising a central processing unit; acounting component for counting the falling seeds inside the seed outlet pipe is further arranged on the seed outlet pipe and is electrically connected to the control component; and the quality detecting device is characterized by further comprising an ultrasonic sensor which is arranged on the seed outlet pipe and used for detecting the seed particle shielding area. The quality detecting deviceis simple in structure, high in principle reliability, not high in cost and suitable for use by common peasants.