A splice protection heater capable of quickly and efficiently performing a fusion process without an excessive heating time, a fusion splicer including the splice protection heater, and a fusion splicing method are provided. The apparatus has a heating part for heat shrinking a protection sleeve that covers a fusion spliced portion of an optical fiber, a plurality of heating elements that can individually heat a plurality of protection sleeves with different timings by being individually turned ON/OFF by switches, or a heating element turned ON/OFF by a switch. This apparatus may also be provided with detecting section that detects whether or not the protection sleeve is set on the heating element, and turns the switch ON/OFF.