A process for producing a photosensitive lithographic plate comprises coating onto a substrate having a hydrophilic surface a solution of a negative working photosensitive composition containing a photosensitive diazo resin and a linear organic polymer dissolved in a solvent mixture comprising:(a) at least 10 wt. % of 1-methoxy-2-propanol,(b) an amino group-free polar solvent having a boiling point under 1 atm of 50.degree. to 100.degree. C. and a dielectric constant at 20.degree. C. of at least 5.5, and(c) 2 to 50 wt. % of methyl lactate,and drying the coated solution.