<p>Novel CoNiCr-based alloys have attracted extensive attention for the development of precipitation strengthened Co-based alloys as candidates for high temperature application. In this work, microstructural stability and oxidation resistance are investigated in a precipitation strengthened CoNiCr-based alloy. The coarsening kinetics of γʹ phase obey Lifshitz-Slyozov-Wagner (LSW) theory, and the calculated activation energy suggests that coarsening kinetics of γʹ phase are controlled by the diffusion of Ni in the matrix. In addition to γ and γʹ phases, the μ phase mainly forms at grain boundaries at 850 and 900&#xa0;°C, while it remains γ/γʹ two-phase microstructure at 950&#xa0;°C in the long-term aging process. Moreover, the alloy exhibits promising oxidation resistance after oxidation at 950&#xa0;°C for 1000&#xa0;h. The oxidation kinetics obey parabolic law with the parabolic rate constant of 1.36 × 10^–6 mg²·cm⁻⁴·s⁻¹, and formation of continuous Cr₂O₃ is effective to enhance oxidation resistance of the Cr-containing alloy.</p> Graphical Abstract <p></p>