Ergodicity depicts a thorough exploration of phase space to reach thermal equilibrium for most isolated many-body systems. Recently, the discovery of persistent revivals in the Rydberg-atom quantum simulator has revealed a weakly ergodicity breaking mechanism dubbed as quantum many-body scars, which are a set of nonthermal states storing the initial quantum information through long-time dynamics in the otherwise thermal spectrum. However, until now, the quantum scars have only been studied in closed systems with Hermiticity. Here, we establish the non-Hermitian quantum many-body scars in open systems and characterize their nature from the entanglement entropy, the physical observable and the energy level statistics. Notably, these signatures of the non-Hermitian scarred states switch from the real-energy axis to the imaginary-energy axis after a real-tocomplex spectra transition, where an exceptional point and a quantum tricritical point emerge simultaneously. We further examine their stability against external fields and establish the whole phase diagram. In the realspectrum region, we reveal that the non-Hermitian scars are more fragile than Hermitian counterparts when increasing the strength of non-Hermiticity. Our results may offer insights on ergodicity-breaking and clues for realizing long-lived coherent states in open quantum many-body systems.

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