The win extended the Frenchwoman's superb record in the Italian capital, where she has reached five of the last six finals.
Zvonareva's record against the second seed did not leave much room for hope.
The 20-year-old Russian, seeded sixth, had lost all six of their previous meetings, including a 6-2, 6-3 defeat at the same stage of last year's Rome event.
Both players began confidently, but Zvonareva's inconsistency from the back of the court cost her dearly. A couple of long groundstrokes and a netted forehand gave Mauresmo a break to establish a 4-2 lead.
From there, the second seed seized control, chasing down a dropshot to flick back a crosscourt winner on the way to breaking for a 5-2 lead and closing out the first set in just over half an hour.
Zvonareva hardly made an ideal start to the second, pushing an easy volley wide then double-faulting on break point to drop serve in the opening game.
Mauresmo's grip on the contest slipped only once, when a pair of double-faults allowed her opponent to draw level at 2-2, but she quickly composed herself, lashed a backhand winner down the line to break back to go 4-3 up and then served out to win.
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