Thunder Force III (サンダーフォースIII) is a scrolling shooter game developed by Technosoft. It is the third chapter in the Thunder Force series. It was released in 1990 in Japan, Europe and the United States for the Sega Genesis. During the same year, it was retooled into an arcade game named Thunder Force AC. In 1991, Thunder Force AC was ported to the Super Nintendo Entertainment System under the title Thunder Spirits.