The news of Miklosko's death was first reported by the iSport.cz website, and confirmed by a post on Ostrava's official X account.
Miklosko was the first Czech goalkeeper to make a breakthrough in England. At West Ham, where he played 318 matches, he became a club legend.
He also featured for QPR and was capped several times by Czechoslovakia and then the Czech Republic national teams.
Miklosko enjoyed huge success after signing for West Ham in 1990, establishing himself as first-choice for over seven years at the Boleyn Ground.
The shot-stopper played a key role in getting the London club promoted from the second tier in his full debut season and was named the 'Hammer of the Year' in 1991.
His strong performances continued throughout his time in England, with Miklosko being named Man of the Match in West Ham's 1-1 draw against Manchester United on the final day of the 1994/95 campaign - a result that played a huge part in Blackburn Rovers clinching the Premier League title.
Miklosko's time at West Ham came to an end in 1998, when he joined Queens Park Rangers, where he would continue playing until retiring in 2001.
Retirement led to a role as a goalkeeping coach with the Hammers, while Miklosko was most recently the sporting director for former club Banik Ostrava.