The agency, which was appointed after a three-way pitch, will be responsible for everything from logistics to video content and production for the two-day event at the end of April.
Some 400 UK independent retailers and their partners will be invited to attend in three groups. Details of the venue are yet to be announced.
Indesit events manager Jayson Weston said: "These annual product launches are key events in our calendar, and we have much to live up to based on last year's success. Line up has come up with some very exciting plans for 2010 designed to add a fresh dimension to the event, and further strengthen our relationships with this crucial audience."
Line Up's appointment comes after the agency ran a highly effective product launch for Indesit in March 2009, which exceeded sales targets by 200%.