Former Hammers midfielder Collison is currently in charge of West Ham's Under-16 side.
Anang, 18, joined West Ham last summer as a scholar and has now agreed a deal that will see him remain at the London Stadium until the summer of 2021.
Youngster Joseph Anang has signed his first professional deal with @WestHamUtd, keeping the goalkeeper in East London until summer 2021 #JosephAnang #NewContract #BrightFuture #AcademyOfFootball #WHUFC #COYI ⚒️⚒️. pic.twitter.com/lhFEGVsSQH— West Ham Matters (@WestHamMatters_) July 1, 2018
The Ghanaian stopper trained with the first team last season and worked alongside Spanish goalkeeper Adrian, as well as Joe Hart who has since returned to parent club Manchester City after a disappointing campaign.
Anang remains quite a way away from first-team football, with 19-year-old Nathan Trott also signing a new deal recently but Collison was delighted to see the Hammers complete a deal to retain Anang.
Still only 29 years of age, Collison has been in charge of West Ham's Under-16 side since being appointed to the role last summer - after earning his coaching badges as a 26-year-old during his spell at Peterborough.
Anang will now be looking to impress new manager Manuel Pellegrini and is likely to work alongside new signing Lukasz Fabianski, when the Polish stopper returns to pre-season after participating at the World Cup.