Yorkshire batsmen Alex Lees and Jack Leaning and wicketkeeper Dan Hodgson have signed contract extensions until December 2015.
Lees, 20, scored his first County Championship century in the win over Middlesex in June.
Leaning, 19, made his first-class debut in the recent draw with Surrey.
Hodgson, 23, has been a regular in the FL t20 this season and featured for the county in the Champions League T20 last year.
"It is very satisfying that we have managed to get them signed up on long-term deals," director of cricket Martyn Moxon told the club website.
"They are progressing nicely into competent cricketers with bright futures at the club for many years to come."