The Aston Villa, Middlesbrough and Sheffield United defender, who retired in 2009, collapsed at Tottenham’s training centre on Thursday, where he was the Under-23 coach.
Ehiogu, who made four appearances for England between 1996 and 2002, received medical treatment on site before being transferred to hospital by ambulance.
A Tottenham statement released on Friday morning read: “We can confirm that Ugo Ehiogu is currently in hospital after collapsing at our Training Centre earlier today.
“Our Under-23’s coach received immediate treatment on site from our medical staff before being transferred to hospital by ambulance."
Ehiogu is survived by his wife, Gemma, and their son, with the club sending their condolences to his family following his sudden death.
“Everyone at the club sends their best wishes to Ugo and his family.
“We shall continue to provide updates when we have further information.”
A secondary statement, released by Spurs on their Twitter account, added: “Ugo received immediate treatment after suffering a cardiac arrest at the training centre yesterday before being transferred to hospital, where he passed away in the early hours of this morning.
“The club sends its deepest condolences to Ugo’s family.
“Gemma has specifically asked that the family are given privacy at this difficult time.
“We should also like to place n record our thanks to all the medical professionals including those at North Middlesex University Hospital, Royal Brompton Hospital and Harefield Hospital for their care and support.”
The former defender was labelled "irreplaceable" by Tottenham's head of coaching and player development, John McDermott.
McDermott added: “Words cannot express the shock and sadness that we all feel at the club. Ugo’s immense presence will be irreplaceable. Our heartfelt sympathies go out to his wife Gemma and his family.”
It is with immense sadness that we announce the passing of Ugo Ehiogu, our Under-23 coach. pic.twitter.com/sSU0yqVfyk— Tottenham Hotspur (@SpursOfficial) April 21, 2017
Villa’s Twitter account paid tribute to Ehiogu, and confirmed that plans are already in place to remember him ahead of this weekend’s Premier League match with Birmingham City.
The club said: “We are deeply saddened to hear of the death of our former defender Ugo Ehiogu.
“Our thoughts are with his family at this terribly sad time.
“We will be holding a minute's applause before our derby with @BCFC... Both sets of players will wear black armbands as a mark of respect.”
Born in Homerton, London, Ehiogu joined the West Bromwich Albion academy and made his first professional appearance for the Baggies in 1989, before joining Villa where he went on to make 237 league appearances for the club between 1991 and 2000.
He moved on to Middlesbrough where he spent seven years at the Riverside, making 126 league appearances, during a spell that also included a loan with Leeds United, before wrapping up his career at Rangers in Scotland and Sheffield United.
Ehiogu’s England debut came in a substitute appearance against China in 1996, and his one and only international goal came against Spain in a friendly at Villa Park in February 2001.
After moving into coaching following his retirement, Ehiogu was part of Peter Taylor’s England Under-20 coaching set-up, before taking up a role with the Tottenham academy in July 2014.