The influence of post-coating heat treatment on the thermal stability and evolving properties of TiAlPN thin film is investigated. Three different annealing temperatures of 350 °C, 550 °C, and 750 °C are used for 1 h in an ambient air and argon atmosphere to study the thermal stability, mechanical, structural, tribological and corrosion properties of the TiAlPN thin films prepared by High Impulse Magnetron Sputtering (HIPIMS). The X-ray diffraction analysis reveals the thermal decomposition and kinetic transformation of fcc-TiAlPN into mixed phases of fcc – TiN and fcc – AlN. Additional peaks of TiO2 and Al2O3 are identified in all the thin films. Broad bands assigned to acoustic, second-order acoustic and optical phonon range vibration modes were observed from the Raman spectroscopy of the as-deposited thin film. The Raman spectroscopy of annealed samples showed additional broad bands associated with the oxide layer. The increase of the annealing temperature from 350 °C to 550 °C enhances the mechanical properties of the TiAlPN thin films, resulting in a maximum hardness of 33.10 GPa, while enhanced adhesion strength is obtained for thin films annealed at 550 °C in an argon atmosphere. The optimal corrosion resistance with corrosion efficiency of 90.11 % and tribology properties are noticed after annealing in ambient air at an annealing temperature of 750 °C.