Abstract Kinetic investigation of the Baudisch reaction indicates that the reaction follows first-order kinetics, and the isokinetic temperature lies at −11°C. Both kinetic studies and product studies require the formation of a phenol-copper-hydroxylamine-hydrogen peroxide complex during the course of the reaction. It was found that the yield of o-nitrosophenol which is the main product of the Baudisch reaction is counterbalanced by that of catechol according to the pH of the reaction system. Maximum yield of o-nitrosophenol is attained in the lower pH region (pH=2.5–3.5). Catechol which is the main product in the higher pH region (pH>4) seems to be produced through the same complex.