To provide a substrate treatment method, capable of forming a coating membrane in a highly reliable manner on the surface of an element substrate where micro-structural body is constituted, and also a substrate treatment method able to divide the substrate highly reliably.

On the substrate 100, where a surface structural body 101' composing an MEMS device is constituted, a resist membrane 120 is formed through the use of the scan coating method. Subsequently, after the resist membrane 120 is patterned, the substrate 100 is divided into multiple dies through dry etching, using the resist membrane 120 as a mask.