To provide a positive photoresist composition having superior sensitivity in the resolution of contact holes in the production of a semiconductor device, the photoresist composition preventing the occurrence of particles in the dissolution of solid components in a solvent or during storage with time and also preventing a variation of sensitivity due to storage with time.

The positive photoresist composition for exposure with far ultraviolet contains: a compound which generates an acid when irradiated with active rays or radiation; a resin having a specified structure and a velocity of dissolution in an alkali developing solution increased by the action of the acid; and a specified mixed solvent.