Patent ID: 8372299

Claim:
A substrate treating method for performing treatment of substrates with a treating liquid, the method comprising the steps of: performing an entire liquid replacement to supply a new supply of treating liquid into an empty treating tank; predetermining and storing an initial life count, said initial life count being predetermined to specify an allowable number of treatments after which a treatment rate of the treating liquid falls within a target range due to treatment of the substrates after said entire liquid replacement; automatically performing treatment of the substrates repeatedly after said entire liquid replacement until reaching said initial life count; after reaching the initial life count, performing a partial liquid replacement, to discharge part of the treating liquid in the treating tank in a predetermined amount and to supply an amount of new treating liquid corresponding to the predetermined amount; and predetermining and storing a normal life count, said normal life count specifying an allowable number of substrate treatments with the treatment rate of the treating liquid remaining within the target range after said partial liquid replacement; and automatically performing treatment of the substrates repeatedly after said partial liquid replacement until reaching said normal life count.