Jean Léon Henri Gouweloos was a Belgian painter, draughtsman, affichiste, and lithographer.

Jean Léon Henri Gouweloos was born in Brussels in 1865 or 1868. Before starting his artistic studies, he lived in Paris, designing posters. He then worked in his uncle's printing press, specialising in art prints.

Like his brother Charles (1867–1946), Jean Gouweloos studied from 1887 to 1890 and from 1893 to 1894 at the Royal Academy of Fine Arts in Brussels. He was a pupil of the painter and decorator Albert Charle and the painter Jean Portaels.

From 1887 he exhibited his works in Brussels, Namur, Ostend, and abroad: Paris (1900 and 1903), Düsseldorf (1904), Berlin (1908), Munich (1913). In 1891, he became a member of the artists' circle 'Voorwaarts'. He was a friend of Victor Gilsoul (1867–1939).

In 1895, he joined the 'Le Sillon' movement.

Gouweloos came to prominence around 1900 when he received praise for his paintings of bathers on the northern coast of Belgium. In addition to seascapes and landscapes, he is best known for his images of magnificent interiors with attractive women, especially portraits and nudes, lost in thought or absorbed in small daily activities.

He also produced two frescoes on the ceiling of the Casino-Kursaal in Ostend and twelve paintings for the Lodge of the Freemasons in Brussels (1900).

During the First World War, from 1914 to 1918, he lived with his family as a war refugee in the Netherlands, first in Domburg and then in Scheveningen. There he often painted beach scenes. In Scheveningen, he was friends with the painter Emmanuel Viérin, who also stayed there as a war refugee.

He died in 1943 in Brussels, or perhaps in Ukkel.