Benjamin Smith Lyman (11 December 1835 – 30 August 1920) was an American mining engineer, surveyor, and an amateur linguist and anthropologist.

Upon returning to the United States, Lyman opened an office as a consulting mining engineer in Philadelphia and worked on surveys from Pennsylvania to Nova Scotia, Arizona and California.

In 1870, Lyman surveyed oil fields in the Punjab region for the Public Works Department of the government of British India, during which he developed an interest in the Far East.

[3] His survey identified the most promising coal fields for Hokkaidō's eventually successful coal industry as well as reporting on progress in the reclamation of waste land; the nature of the soil in various districts; the customs, physique, and folklore of the Ainu people; useful ores and stones; the development of hydraulic power; importation of foreign capital; and the advantage of cooperation with foreign concerns in the mining industry.

He attended meetings of technical and scientific societies as well as the Oriental Club of Philadelphia, and held a reception each year on the birthday of the Emperor of Japan.

Although he officially retired in 1895, Lyman made a journey (1906–07) to survey the coal lands near Mount Lantauan on Cebu in the Philippines, for a New York City company that was building a railroad there.