The unnamed member of coaching staff member at the club’s academy returned a positive result as a part of routine testing procedures in place for all clubs.
The first-team are due to report back for testing and health screening at Rush Green on Sunday ahead of pre-season training on Monday.
A West Ham spokesperson said: “We can confirm that a member of our backroom staff within the Academy has tested positive for Covid-19. The individual, whose identity will remain private due to medical confidentiality, is asymptomatic and currently self-isolating in line with guidance.”