The high fraction of indium (In) in the multi-quantum wells (MQWs) and the large lattice mismatch between InN and GaN dramatically decrease the stability of InGaN-based green light emitting diodes (LEDs). Because the growth temperature of p-GaN is much higher than that of MQWs, the growth of p-GaN will impact the quality of MQWs greatly. In this work, it is focused on the influence of the growth temperature and the thickness of p-GaN on the performance of green LEDs, and it is revealed that too high growth temperature or thickness will have negative impact on the stability of In fraction in MQWs, which results in the broadening of emission peak and the reduction in luminous efficiency. Accordingly, the optimized growth temperature and thickness are proposed. Furthermore, the influence of MQWs protection layer on green LEDs performance was discussed and it is found that this protection layer is beneficial to the stability of the emission wavelength of green LEDs.