Moustapha Seck (born 23 February 1996) is a Senegalese professional footballer who plays as a left back for Almere City, on loan from Roma.
Born in Dakar, Senegal, Seck moved to Barcelona in Spain when he was five years old. He began playing football with his local football club before being picked up by Barcelona in 2005, and spent eight years in the club's Cantera. In 2013, Seck sought a new challenge and elected to follow in the footsteps of compatriot and former Barcelona teammate Keita Baldé and sign for Serie A side Lazio. At Lazio, Seck played for three seasons between the club's academy and reserve sides and won three titles before being released in 2016 following contractual disagreements with management.
Following the expiration of his contract with Lazio, Seck signed as a free-agent for local rivals Roma. On 9 December 2016, manager Luciano Spalletti handed him his debut in a 0–0 Europa League draw with Astra.