Pieter de Vries (1897 – November 1975) was a Dutch trade union leader.
[1] In 1947, de Vries was elected as president of the Netherlands Seafarers' and Fishermen's Union.
The following year, he was additionally elected as president of the International Mercantile Marine Officers' Association, although this organisation was largely inactive, so the role involved little work.
He also became prominent in the International Transport Workers' Federation (ITF), becoming the chair of its Fishermen's Section.
The ITF's general secretary, Omer Becu, left to take a new role in 1960, and with his backing, de Vries was narrowly elected as his successor.