The Congo international’s performances for the South London outfit have often verged upon talismanic, notching up nine goals and nine assists during the last two Premier League campaigns.
But Mirror Football claim the recent arrival of Andros Townsend, who signed at Selhurst Park on Friday, could see the Eagles decided to cash in on the dynamic winger.
Everton, Liverpool, Manchester United and Tottenham Hotspur have been credited with interest in Bolasie previously and have reportedly asked to be kept informed of any developments.
But West Ham are said to be most interested in the 27-year-old, who plied his trade with Plymouth Argyle and Bristol City before signing for Palace in summer 2012.
And the Hammers boast a significant advantage over some of the aforementioned suitors because Bolasie is keen to stay in London, where his family are firmly settled.