His penalty against Genoa two weeks ago brought the 37-year-old level with Gunnar Nordahl on 225 goals and, after missing the mark at Udinese last week, Totti followed up Erik Lamela's opener to reach a long-awaited personal milestone.
And with city rivals Lazio losing at Torino, and Inter Milan's game at Sampdoria postponed due to bad weather, the Giallorossi used the invaluable win to close within four points of Fiorentina as an unlikely push for Champions League qualification gathers pace.
It was initially unclear who had fired Roma ahead in the seventh minute, with both Lamela and Alessandro Florenzi involved as Daniele De Rossi's cross was scrambled over the line.
Replays, however, confirmed the Argentinian had scored his 13th goal of the season.
Totti, meanwhile, was a man on a mission to leave Nordahl on his own in third place on the all-time list but visiting goalkeeper Antonio Mirante thwarted the veteran early on with two quick reflex saves.
Totti then set Marquinho free down the left channel with a deft backheel flick, the Brazilian finding Simone Perrotta to dig out a ripping strike to rattle the crossbar.
It was all hands to the pump for a disorganised Parma side and the visitors had Alessandro Lucarelli to thank for clearing the ball off Marquinho's boot as he prepared to slot home in the 28th minute.
Despite navigating their way to the break without further incident, Parma were firmly under the cosh following the restart and it took Totti just two minutes to hit the bar, and then a post, from an angled free-kick.
The Gialloblu enjoyed a rare purple patch around the hour mark, however, with Nicolas Burdisso coming to Roma's rescue with a critical block.
When Gabriel Paletta headed against the bar with goalkeeper Maarten Stekelenburg beaten, Burdisso covered Marco Parolo's quick feet to deflect the follow-up into the stands and to safety.
Marquinhos stole the ball from Nicola Sansone to defuse the Parma raid and two minutes later the Stadio Olimpico erupted as Totti made history.
Jaime Valdes conceded a free-kick in shooting range and Totti duly obliged with a searing daisy-cutter to beat Mirante and draw him one goal closer to Silvio Piola's imposing record of 274 goals.
Mirante then kept out goal number 227 with his feet as the game entered its final phase, just minutes after Amauri had failed to surprise Stekelenburg with an acrobatic effort, but the damage was done and the history made in the capital city.