François-Louis-David Bocion (30 March 1828, Lausanne – 13 December 1890, Lausanne) was a Swiss artist and teacher.
Bocion studied art in Lausanne before going to Paris, France, in 1845 to study further. In Paris he worked together with the Swiss painters Charles Gleyre and Louis-Aimé Grosclaude. Following a bout with typhoid fever, he returned to Lausanne in 1848. During the early part of his career, Bocion's interest was in the field of illustration as well as in painting historical subjects. However, influenced by the landscapes of Jean-Baptiste-Camille Corot, he began painting scenes from around Lake Geneva for which he is best remembered.
In 1849 Bocion secured a professorship at the Lausanne École Industrielle, a position he held for over forty years. During his time there, Théophile Steinlen and Eugène Grasset, both natives of Lausanne, were his pupils and he encouraged them to expand their knowledge by moving to work and study with the burgeoning art community in Paris. Bocion visited Rome in 1852 and he went to Paris again in 1855 and 1859. Between 1879 and 1883 he spent some time in the area of Venice, where he also made some of his well-known paintings.
During his life Bocion were exhibited at many exhibitions in Switzerland and abroad, such as the World exhibition of 1873 in Vienna and the World exhibition of 1885 in Antwerp.