The 21-year-old product of Barcelona's youth academy will undergo a medical before signing on Friday, according to SID sources.
One of the most exciting young talents in Europe, the attacking midfielder has been on the wish list of Leipzig head coach Julian Nagelsmann since June last year when he helped Spain win the 2019 European Under-21 title, scoring in the 2-1 final win over Germany.
Olmo scored on his debut for the senior Spain team last November as a second-half replacement in a 7-0 thrashing of minnows Malta in a Euro 2020 qualifier.