A new more precise measurement of the ground-state proton decay of La is presented [E =806(5) keV, t=26(3) ms]. La was produced via the p4n fusion-evaporation channel by bombarding a Zn target with 310 and 295 MeV Ni beams. The proton decay rate is consistent with emission from a prolate deformed 3/2 or 3/2 Nilsson state. No evidence is found for a previously reported proton decay from a high spin isomer in La. An upper limit for the production cross section for proton decay of La at a bombarding energy of 325 MeV was established.