Lovell went to stumps on day three unbeaten on 146 after crafting a patient innings at Cricket Central in western Sydney.
Queensland started Sunday at 2-96, but finished it at 5-406 thanks to Lovell's heroics.
The 25-year-old put on a 310-run stand with Ben McDermott (87 off 143 balls, including 12 fours) as Test quick Josh Hazlewood (0-57) failed to snare a breakthrough.
All of the Bulls' top-six got starts as they raced past NSW's first-innings total of 239.
Lovell made NSW pay for letting slip two chances during his knock.
Jack Edwards put down Lovell when he was on 22 off Hazlewood's bowling.
The fifth-gamer was given another life on 53 when Oliver Davies dropped a catch at first slip.
His unbeaten century continues a superb game for Lovell, who took 3-13 with the ball from just 4.3 overs to clean up the hosts' tail.
There is unlikely to be an outright result after two sessions on Saturday were lost to rain.Â
Test opener Usman Khawaja's half-century provided the highlight on Saturday, with former Australia batter Matt Renshaw not capitalising on a start to be dismissed for 25.
35°C