Metal halide perovskites (MHPs) have been demonstrated to exhibit mixed ionic and electron conductive properties, characterized by their remarkable soft lattice features. However, the complicated interplay between ion, lattice, and carrier recombination and the influence on the optoelectronic properties and performance of perovskite solar cells are elusive. To this end, using time-dependent photoluminescence (PL) spectroscopy to investigate the Light Soaking effect of organic-inorganic perovskite solar cells doped with alkali metal ions (K+/Rb+) and undoped perovskite films under continuous illumination. Dynamic monitoring of PL intensity and carrier lifetimes within 1-500 seconds of continuous illumination revealed significant influences of alkali metal ions and light intensity on the performance, including stability of the perovskite solar devices. The results reveal that K+/Rb+ doping in perovskite films induces more positive effects on Light Soaking. These effects include enhanced PL intensity, inhibited phase separation, and prolonged carrier lifetime. The synergistic combination of these effects leads to improved photoelectric conversion efficiency and device stability of perovskite solar cells (PSCs). These findings offer novel insights into the roles of ions in MHPs and are pivotal for comprehending the mechanisms underlying MHPs devices, particularly concerning the ionic properties of MHPs.