The embodiment of the invention discloses a testing method and device for film thickness and relates to the field of testing. The cost for measuring the film thickness can be reduced while the testing precision is ensured. The testing method for the film thickness comprises the following steps: enabling a testing mask to cover on the surface of a substrate, wherein the testing mask is provided with a plurality of hollows; performing sputter coating on the substrate on which the testing mask covers; removing the testing mask; and performing measurement by utilizing a probe method.