Lajos Kunffy was born in Orci, a village in south-western Hungary near the Croatian border. He attended law school and the Mintarajziskola (National University of Fine Art) in Budapest in 1887 while taking painting classes with Pál Vágó.  Kunuffy studied at the school of Simon Hollósy, then attended the Munich Academy of Painting for six months in 1891. That same year he moved to Paris to study at Académie Julian under Jean-Paul Laurens and Jean-Joseph Benjamin-Constant. Kunffy participated in several exhibitions in the city, most notably the Salon d'Automne and the Société National des Beaux Arts show. He also exhibited at the National Millennium Exhibition in Budapest in 1896 and at the Kunsthalle in 1900. Kunffy was awarded the French Legion of Honor in 1905.

Though Kunffy maintained a residence in Paris, he summered on his family estate in Somogytúr. His scenes of village life proved popular in the city. In 1913, he exhibited at the Galerie Georges Petit. In 1930 he was made a ministerial commissioner for cultural diplomacy in Serbia and Romania, and permanently moved to Somogytúr, though he continued to travel around the Dalmatian coast. After World War II Kunnfy resumed exhibiting, showing independently in Kaposvár, then in Budapest with Oszkár Glatz at the Ernst Museum in 1953, and in a solo exhibition at the Rippl-Rónai Museum in 1956. The Order of Merit of Labor and the title of Meritorious Artist were bestowed on Kunffy in 1959 and 1960 respectively, and his former estate now houses the Kunffy Lajos Memorial Museum.

Kunffy paintings reside in the collections of the Hungarian National Gallery, Rippl-Rónai Museum and the Kunffy Lajos Memorial Museum. A catalogue for his exhibition at the Hungarian National Salon in 1924 has been digitized and was published by the Metropolitan Museum of Art.