Quantum coherence in quantum optics is an essential part of optical information processing and light manipulation.Alkali metal vapors,despite the numerous shortcomings,are traditionally used in quan-tum optics as a working medium due to convenient near-infrared excitation,strong dipole transitions and long-lived coherence.Here,we proposed and experimentally demonstrated photon retention and subsequent re-emittance with the quantum coherence in a system of coherently excited molecular nitro-gen ions(N2+)which are produced using a strong 800 nm femtosecond laser pulse.Such photon retention,facilitated by quantum coherence,keeps releasing directly-unmeasurable coherent photons for tens of picoseconds,but is able to be read out by a time-delayed femtosecond pulse centered at 1580 nm via two-photon resonant absorption,resulting in a strong radiation at 329.3 nm.We reveal a pivotal role of the excited-state population to transmit such extremely weak re-emitted photons in this system.This new finding unveils the nature of the coherent quantum control in N2+ for the potential platform for optical information storage in the remote atmosphere,and facilitates further exploration of funda-mental interactions in the quantum optical platform with strong-field ionized molecules.