A novel red SrLaGaO4: Eu3+ phosphor was successfully synthesized by solid-phase sintering method. X-ray diffractometer characterization shows that the phosphor possesses a tetragonal phase with a space group of I4/mmm. XPS spectroscopy characterized the chemical composition and the presence of trivalent europium in samples. Under 395 nm excitation, the emission spectra showed one strong peak at 618 nm subjected to electronic transition of 5D0→7F2. The quantum yield of the SrLaGaO4: 0.3Eu3+ is 90.9%. At 423 K, the luminous intensity of SrLaGaO4: 0.3Eu3+ phosphor is 60.9% of the initial value. Besides, the chromaticity coordinates of SrLaGaO4: 0.3Eu3+ is (0.6467, 0.353) and the color purity is 99.56%. Finally, white LED with chromaticity coordinates of (0.36, 0.37) was prepared by mixing sample with commercial green/blue phosphors. In conclusion, SrLaGaO4: Eu3+ phosphor is a very promising light-emitting material for WLED devices.