Marjan op den Velde (born 9 January 1971) was a Dutch water polo player.
She was a member of the Netherlands women's national water polo team.
She competed with the team at the 2000 Summer Olympics.
She was also part of the national team at the
1991 World Aquatics Championship,1998 World Aquatics Championships, 1999 Women's European Water Polo Championship and 1999 FINA Women's Water Polo World Cup.