Jan Voerman, also known as Jan Voerman Sr., was a Dutch painter.

Voerman was born in Kampen and died in Hattem.

Voerman studied at the Rijksakademie van Beeldende Kunsten in Amsterdam and the Royal Academy of Fine Arts Antwerp under Charles Verlat. He admired the work of his contemporary George Hendrik Breitner. Around 1900, Voerman painted the clouds above the IJssel river. In Hattem, many of his works can be seen in the Voerman Museum Hattem.

He married Anna Henriette Gezina Verkade, daughter of Ericus Gerhardus Verkade–founder of the Verkade company in Zaandam–and Eduarda Thalia Koning, on 1 October 1889 in Amsterdam. Verkade was the sister of Jan Verkade, who at the end of the 1880s was Voerman's apprentice. Voerman and Verkade had two sons, Jan Voerman Jr. (1890–1976) and Tijs Voerman (1891–1970), who both also became illustrators.