Returning to the Marianas, Princeton again struck Pagan, Rota and Guam, then replenished at Eniwetok. On 14 July, she got underway again as the fast carriers returned their squadrons to the Marianas to furnish air cover for the assault and occupation of Guam and Tinian. On 2 August, the force returned to Eniwetok, replenished, then sailed for the Philippines. Enroute, its planes raided the Palaus, then on 9-10 September, struck airfields on northern Mindanao. On the 11th, they pounded the Visa yas. At mid-month the force moved back over the Pacific chessboard to support the Palau offensive, then returned to the Philippines to hit Luzon, concentrating on Clark and Nichols fields. The force then retired to Ulithi, and in early October, bombed and strafed enemy airfields, installations and shipping in the Nansei Shoto and Formosa area in preparation for the invasion of the Philippines.
On the 20th, landings were made at Dulag and San Pedro Bay, Leyte. Princeton, in TG 38.3, cruised off Luzon and sent her planes against airfields there to prevent Japanese land based aircraft attacks on Allied ships massed in Leyte Gulf. On the 24th however, enemy planes from Clark and Nichols fields found TG 38.3 and reciprocated. Shortly before 1000, a lone enemy dive-bomber came out of the clouds above Princeton. At 1500 feet the pilot released his bomb. It hit between the elevators , crashed through the flight deck and hanger, then exploded. Initial fires soon expanded as further explosions sent black smoke rolling off the flight deck and red flames along the sides from the island to the stern. Covering vessels provided rescue and fire-fighting assistance and shielded the stricken carrier from further attack. At 1524, another, much heavier explosion, possibly the bomb magazine, blew off the carrier's stern and with it the after flight deck. Birmingham (CL-62), alongside to fight fires, suffered heavy damage and casualties.
Efforts to save Princeton continued, but at 1604 the fires won. Boats were requested to take off remaining personnel and shortly after 1706, Irwin (DD-794) began to fire torpedoes at the burning hulk. At 1746, Reno (CL-96) relieved Irwin and at 1749 the last, and biggest, explosion occurred. Flames and debris shot up 1000-2000 feet. Princeton's forward section was gone. Her after section appeared momentarily through the smoke. By 1750 she had disappeared, but 1,361 of her crew survived. Included in that number was Capt. John M. Hoskins, who had been prospective commanding officer of CVL-23 and lost his right foot with her, but who, despite the loss, would become the 1st commanding officer of the fifth Princeton(CV-37).
Losses and damage to assisting vessels were heavy: Birmingham--85 killed 300 wounded, a heavily damaged topside, and loss of 2 5", 2 40mm. and 2 20mm. guns; Morrison (DD-560)--foremast lost, portside smashed; Irwin--forward 5" mounts and director out, starboard side smashed; and Reno--one 40mm. smashed.
Princeton earned 9 battle stars during World War II.