The 22-year-old striker will officially complete a move at the end of his Fratton Park contract on 1st July.
He has been allowed to move on by Portsmouth after just six months back in English football.
The former Birmingham City trainee, who has previously caught the eye while on loan at Swindon Town, Preston North End and Carlisle United, spent nine months in Turkey with Elazigspor prior to joining Pompey.
A number of Football League clubs were keen on snapping him up once it was revealed that he was to become a free agent this summer, but it is Ross County who have secured his services.
Manager Derek Adams said in the Daily Record: “We had to compete with a number of good English league clubs for Jake’s signature so I’m delighted to have him on board.
“He’ll be a great addition to our squad for next season.”