This study reports the realization of intrinsic 2D hard ferromagnetism in van der Waals (vdW) Fe3GaTe2 nanoflakes down to the monolayer limit. The Fe3GaTe2 monolayer exhibits a record-high Curie temperature (Tc) of 240 K, which is the highest reported for known intrinsic vdW ferromagnetic monolayers. The material demonstrates robust perpendicular magnetic anisotropy (PMA) with square-shaped hysteresis loops and negative magnetoresistance (NMR) behavior under an applied out-of-plane magnetic field. These properties are attributed to the intrinsic mechanism stemming from the Berry curvature of electronic bands, which dominates the anomalous Hall effect (AHE) in the low-temperature range. The study also shows that the Curie temperature decreases monotonically as the sample thickness decreases from 5 layers to 1 layer, but remains relatively high in the monolayer limit. The results provide an excellent candidate material for next-generation spintronic applications and open up new opportunities for exploring physical mechanisms in 2D ferromagnetism. The study was supported by the National Key Research and Development Program of the Ministry of Science and Technology of China, the National Natural Science Foundation of China, and the Innovation Program for Quantum Science and Technology.This study reports the realization of intrinsic 2D hard ferromagnetism in van der Waals (vdW) Fe3GaTe2 nanoflakes down to the monolayer limit. The Fe3GaTe2 monolayer exhibits a record-high Curie temperature (Tc) of 240 K, which is the highest reported for known intrinsic vdW ferromagnetic monolayers. The material demonstrates robust perpendicular magnetic anisotropy (PMA) with square-shaped hysteresis loops and negative magnetoresistance (NMR) behavior under an applied out-of-plane magnetic field. These properties are attributed to the intrinsic mechanism stemming from the Berry curvature of electronic bands, which dominates the anomalous Hall effect (AHE) in the low-temperature range. The study also shows that the Curie temperature decreases monotonically as the sample thickness decreases from 5 layers to 1 layer, but remains relatively high in the monolayer limit. The results provide an excellent candidate material for next-generation spintronic applications and open up new opportunities for exploring physical mechanisms in 2D ferromagnetism. The study was supported by the National Key Research and Development Program of the Ministry of Science and Technology of China, the National Natural Science Foundation of China, and the Innovation Program for Quantum Science and Technology.