Adrianus Lambertus Joseph "Bob" Maas (18 October 1907 – 17 December 1996) was a sailor from the Netherlands, who represented his native country at the 1932 Summer Olympics in Los Angeles and took the Silver medal.

The Maas brothers took part at their own cost.

In 1936, with Willem de Vries Lentsch as crew, Maas took part in the Dutch Star BEM II and took the Bronze.

During the 1948 Summer Olympics Bob Maas also took a Bronze medal in the Star.

His last Olympic appearance was in 1952 again with Eddy Stutterheim as crew.