Geertruida Christina "Truus" Baumeister (21 October 1907 – 25 December 2000) was a Dutch freestyle swimmer who won a gold medal in the 4 × 100 m relay at the 1931 European championships.

The Dutch team of Eva Smits, Maria Vierdag, Marie Braun and Baumeister came in a close third, but were disqualified because Baumeister had jumped to early in the water at her changeover.

[2][3] Baumeister made amends in 1931 when she and her team won gold in the 4 × 100 m relay at the 1931 European championships, beating the closest competitors by six seconds.

She was born in Rotterdam as the daughter of Arnold Carl Theodor Baumeister and Geertruda Elisabeth Dielissen.

[4][5] She emigrated with the name "Gertrude Hoftyzer" to the United States in December 1946, where she joined her husband who had taken residence on 78th Street in Brooklyn, New York, in May of that year.