The QPR striker opened the scoring in the 2-1 win at Charlton Athletic in the 34th minute with an unmarked finish from Daryl Murphy's cut-back pass before the provider turned scorer to give the Tractor Boys a two-goal lead at the break.
Danny Haynes' 72nd minute penalty pulled one back for the Addicks but the damage had already been done.
Campbell missed an earlier chance of his own from the spot but was still praised by manager Mick McCarthy after his second last appearance before heading back to Loftus Road.
"We got good quality goals. DJ persisted after the miss and took his very well," he said.
"They put us under pressure in the second half. They have two good centre-forwards who gave us a lot of problems but we persisted and held on."
Campbell's final showing for Ipswich will be Saturday's trip to Wolves.