A synthetic method to prepare a wide range of 2H-indazoles was developed via a tandem Pd-catalyzed deacylative cross-coupling reaction of 2-iodoazoarenes and 2-iodoaryltriazenes with acyldiazoacetates and denitrogenative cyclization reaction of in situ generated diazoacetates having azoaryl and triazenyl aryl moieties in one-pot. Additionally, azoaryl-substituted diazoacetates underwent Pd-catalyzed denitrogenative cyclization to produce 2H-indazoles. The present reaction is a good example in which a Pd(0)-catalyst is involved in two catalytic cycles in one-pot. This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (2011-0018355), 2015H1C1A1035955.