Sir Henry Simpson Lunn (30 July 1859 – 18 March 1939) was an English humanitarian and religious figure, and also founder of Lunn Poly, one of the UK's largest travel companies.

Lunn was born in Horncastle, Lincolnshire, elder son of greengrocer Henry Lunn and Susanna, daughter of Simpson Green. His parents were both devout Wesleyan Methodists and their son was raised in that tradition. He gained a place at Horncastle Grammar School. He attended Headingley College, Leeds, for instruction to become a church minister and was ordained in 1886. He also trained as a medical doctor at Trinity College, Dublin. His marriage to Mary Ethel Moore, the daughter of a canon, produced four children: alpine skiing pioneer Arnold Lunn, writers Hugh Kingsmill Lunn and Brian Lunn, and a daughter who predeceased him.

After one year of missionary service in India, he was forced to return in 1888 to Lincolnshire after contracting an illness. His criticism of the conditions for Methodist missionaries in India led him to conflict with his fellow ministers, and he sought to explore wider horizons. He concentrated on his religious belief of Christian unity and cooperation, which was a forerunner of the Ecumenical Movement. As such, he was the founder of the Co-operative Educational Tours in 1893 and organized meetings of predominantly English church leaders at the annual Grindelwald Reunion Conferences, between 1892 and 1896. In 1902, he organised his first inclusive tours at Adelboden and Wengen, Switzerland, which started the trend for British visitors to combine a religious/health retreat with winter sports. Many Anglican churches were established at fashionable winter resorts.

In 1905 he formed the Public Schools Alpine Sports Club which secured the use of major hotels and the sanatorium at Le Beauregard. With Lord Bryce, he founded the Hellenic Travellers Club in 1906 and this success led his second company, Alpine Sports Limited, founded two years later, to open up many winter sports resorts by organising tours.

In 1908 he convened a meeting at the Devonshire Club to found the Alpine Ski Club, a gentleman’s club for ski-mountaineers.

He was a vocal opponent of the Boer War but remained in the confidences of leading politicians. He became a Knight Bachelor in 1910 and was active in Liberal politics, forming a strong friendship with Asquith. He stood twice for Parliament in 1910 for Boston and 1923 for Brighton, but was unsuccessful. In 1924 he was the first Editor of "The Review of The English Churches". The first edition was published in January of that year and included an article on Birth Control and Prohibition in The United States. He helped form the Irish Protestant Home Rule Association. Although he continued to travel and promote his vision of the union of churches with the League of Nations, his company (renamed as Sir Henry Lunn Travel) grew to become one of the largest travel agents in Britain. During the 1960s the company was merged with the Polytechnic Touring Association to form Lunn Poly.

He wrote two autobiographical works: Chapters from My Life (1918) and Nearing Harbour (1934). He died at the Hospital of St John and St Elizabeth in St John's Wood.