Abstract: A photolithography process using a photoresist is as following. A substrate is provided for coating a photoresist thereon to form a photoresist layer and the photoresist is formed by mixing photocatalyst particles and polymer binder in a solvent. The photoresist layer is well-adhesive and has good mechanical strength. A light is illuminated on the photoresist layer through a photo mask having a pre-designed pattern thereon. Then, the portion of the photoresist layer where the light projects is removed by water or another environment-friendly solvent so as to reduce the harmful waste produced in the processes.