Gvardiol, 18, has only made 13 appearances for Dinamo’s first team but is considered an enormous talent in Croatia.
Bayern Munich have had a confirmed interest in Gvardiol, a sign of his potential.
Gvardiol, a left-footed centre-back, should join Leeds for a fee of around €20m.
He will follow another central defender, Germany international Robin Koch, to Elland Road.
Marcelo Bielsa is spending heavily this summer to ensure Leeds’ long awaited return to the Premier League isn’t a short stay.
The Yorkshire club broke their long-standing club record transfer fee to sign Spain striker Rodrigo Moreno last week.