Armand Guillaumin (born February 16, 1841 - died June 26, 1927, was a French impressionist painter and lithographer.

Born Jean-Baptiste Armand Guillaumin in Paris, France, he worked at a relative's lingerie shop and for a French government railway before studying at the Académie Suisse in 1861. There, he met Paul Cézanne and Camille Pissarro with whom he would maintain a lifelong friendship. While he never achieved the stature of these two, his influence on their work was significant and Cézanne made his first attempt at etching based on one of Guillaumin's paintings of barges on the River Seine.

Guillaumin exhibited at the Salon des Refusés in 1863 and later became a friend of Vincent van Gogh whose brother, Theo sold some of his works. Noted for his intense colors, Guillaumin's works are significant in art history and can be found at major museums around the world. He is most remembered for his landscapes of Paris, the Creuse département, and the area around Les Adrets-de-l'Estérel near the Mediterraneran Coast in the Provence-Alpes-Côte d'Azur region of France.

Armand Guillaumin died in 1927 in Orly, Val-de-Marne just south of Paris.