The embodiment of the invention provides a user detection method and apparatus. The method comprises the following steps: extracting a part of users from a target user pool to serve as a detection user group of tth iteration, wherein the target user pool comprises a plurality of users using a target resource block, and the target source block is any resource block in a system bandwidth, and the initial value of the t is 1; performing MPA receiving detection on the users in the detection user group of the tth iteration, and continuing to execute the step of extracting part of users from the target user pool to serve as the detection user group of the tth iteration, wherein once the step of extracting part of users from the target user pool to serve as the detection user group of the tth iteration is executed, 1 is added to the t. therefore, by adoption of the user detection method and apparatus provided by the embodiment of the invention, the detection complexity of an MPA receiver canbe reduced.