Arthit Kamlang-ek (31 August 1925 – 19 January 2015; Thai: อาทิตย์ กำลังเอก, Thai pronunciation: [ʔaːtʰít kamlaŋʔèːk]) was a Thai general. He was the Commander-in-Chief of the Royal Thai Army from 1982 to 1986 and parallel the Supreme Commander of the Royal Thai Armed Forces from 1983 to 1986. He was particularly influential during the 1980s during the government of Prem Tinsulanonda.