Effect of entropy on the properties of the proto neutron star (PNS) PSR J0348+0432 is studied in the framework of relativistic mean field theory under neutrino trapping. As the entropy per baryon increases from S = 1.0 to S = 2.0, the radius of the PNS PSR J0348+0432 increases from R = 13.41–12.46 km to R = 14.46–13.56 km, which implies an increase of approximately 8%–9%. However, the effect of entropy on the center relative particle density of neutrons and Λs is small. As the entropy per baryon increases from S= 1.0 to S= 2.0, the center relative particle density of Σ−, Σ0 and Σ+ increase by approximately 3000–2 times, 100–20 times and 4–1 times, respectively. The relative particle density of Ξ− and Ξ0 also increase with the increase of that in entropy. The center relative particle density of Ξ0 increases by approximately 13–2 times as the entropy per baryon increases from S= 1.0 to S= 2.0. Therefore, entropy exerts a significant impact on the center relative particle density of Σ− and Ξ0.