Lucia Paulina Keijser (1875-1958) was a Dutch painter known for her floral still lifes.
Keijser was born on 9 December 1875 in Amsterdam. She studied at ' (National Normal School for Drawing Teachers) in Amsterdam. She was taught by and Jan Derk Huibers. Keijser was married twice; first to G. L. Wittig and after his death to R. Ruijneman.
Keijser's work was included in the 1939 exhibition and sale Onze Kunst van Heden (Our Art of Today) at the Rijksmuseum in Amsterdam. She was a member of ' (The Independents) and ' (Association for Visual Arts Laren-Blaricum).
Keijser died on 26 January 1958 in Laren, North Holland.