The Rhinos say the working partnership will include player exchange under the dual registration scheme as well as media and marketing.
Leeds chief executive Gary Hetherington said: "I see this as a real chance for both clubs to work together for the benefit of rugby league across Leeds."
He added: "I'm sure some fans will view this as Hunslet becoming a feeder club for us but when you look at the reality of the situation it will actually be the Rhinos who are sending players to them."
Hunslet are currently under the control of the Hunslet Independent Supporters Trust.
Hunslet chairman Neil Hampshire said: "I'd like to reassure our fans that this in no way affects our independence and it's more about how we can learn and grow as a club in the local community to be able to meet our long-term goals.
"It's the reality of where we are right now and I'm certain that more Super League and Championship clubs will start to 'twin' together in the near future."
The partnership will begin with immediate effect, although player movement will not start until next season.