William Henry ("Wee Willie") Dammann (August 9, 1872 – December 6, 1948) was an American left-handed Major League Baseball pitcher.

A native of Chicago, he played for three seasons in Major League Baseball, all of them with the Cincinnati Reds.

In his three seasons, he went 24–15 in 60 games where, starting 38 games and completing 26 with four shutouts.

On July 9, 1902, Dammann, pitching for the Southern Association's Nashville Baseball Club, pitched a 5-inning no-hitter against the Shreveport Giants at Athletic Park in Nashville.

This biographical article relating to an American baseball pitcher born in the 1870s is a stub.