塞缪尔·皮尔庞特·兰利（Samuel Pierpont Langley，1834年8月22日－1906年2月27日），美国天文学家、物理学家，航空先驱，测热辐射计的发明者。

兰利1834年出生于美国马萨诸塞州的诺克斯包利，早年未受过高等教育，从波士顿拉丁文学校毕业后进入哈佛大学天文台成为助教。1881年，他发明了测热辐射计，可以用于微量热的精密测量。兰利用它仔细测定了太阳在可见光波段和红外波段的辐射强度，并首次将太阳辐射的测量扩展到远红外波段。1886年，兰利由于太阳物理方面的贡献，获得美国科学院颁发的亨利·德雷伯奖。1887年，兰利成为史密松学会的第三任秘书长，1890年创办了史密松天体物理台。

Samuel Pierpont Langley (/ˈlæŋli/; August 22, 1834 – February 27, 1906) was an American astronomer, physicist, inventor of the bolometer and pioneer of aviation. He attended Boston Latin School, graduated from English High School of Boston, was an assistant in the Harvard College Observatory, then moved to a job ostensibly as a professor of mathematics at the United States Naval Academy, but actually was sent there to restore the Academy's small observatory. In 1867, he became the director of the Allegheny Observatory and a professor of astronomy at the Western University of Pennsylvania, now known as the University of Pittsburgh, a post he kept until 1891 even while he became the third Secretary of the Smithsonian Institution in 1887. Langley was the founder of the Smithsonian Astrophysical Observatory.