The present invention relates to a monitor wafer measuring method and measuring apparatus. The monitor wafer measuring method comprises the following steps: fixing a product wafer, the product wafer having several alignment marks and product measuring sites corresponding respectively to the alignment marks; determining the product measuring sites according to the alignment marks; and placing a monitor wafer, a projection of the monitor wafer in a vertical direction being aligned with and coinciding with the product wafer. The present application can reduce or even eliminate positional errors of the monitor wafer during a measurement process, such that product-level measuring position accuracy can be achieved for the monitor wafer and further, the measuring machine itself and process changes can be monitored in a better way.