In this study, an intermediate monomer and a branched tris (diethylamino) phosphine (TDP) were employed in a CsPbBr3 perovskite nanocube solution to synthesize CsPbBr3 perovskite nanorods, ensuring both the slow growth rate and the orientation growth. Transmission electron microscopy, X-ray diffraction, ultraviolet-visible absorption spectroscopy, and photoluminescence (PL) spectroscopy were used to characterize the obtained material. It is found that the CsPbBr3 perovskite nanorods exhibit good crystal quality, low defect density, and favorable optical property. The gain coefficient (860 cm -1) and threshold (17.5 μJ/cm 2) were measured through the variable length stripe method and PL spectra under different pumping densities. Furthermore, the photostability of the sample at a high temperature and high relative humidity (85 ℃, 85%RH) was tested. It is found that the stability improved. Results provide experimental basis for the practical application of advanced perovskite-based lasers.