Australia's Richie Porte captured his second Paris-Nice title, overhauling a 36-second deficit on the final day.
Frenchman Tony Gallopin had stretched ahead after winning Saturday's sixth stage, and was bidding to become the first home winner for 18 years.
But Team Sky's Porte, 30, won Sunday's 9.6km time-trial on the Col d'Eze in 20 minutes 23 seconds, with Gallopin 1:39 adrift in sixth spot overall.
World champion Bradley Wiggins, who was in 103rd place, withdrew beforehand.
In unusually cold and wet weather, Porte finished the early season classic stage race 30 seconds clear of Michal Kwiatkowski, the Polish world road-race champion, who opened the race by winning the prologue outside Paris last Sunday.
Slovenian Simon Spilak took third place overall after finishing second in the time trial.
Porte became the first Australian winner of the 'Race to the Sun' when he triumphed in 2013.
"I relish this win even more than two years ago," the Tasmanian-born rider said. "In between times I had a bad season."
Stage seven result
1. Richie Porte (Aus/Team Sky) 20 minutes 23 seconds
2. Simon Spilak (Slo/Katusha) +13secs
3. Rui Costa (Por/Lampre) +24secs
4. Tony Martin (Ger/Etixx - Quick-Step) +29secs
5. Michal Kwiatkowski (Pol/Etixx - Quick-Step) Same time
6. Andrew Talansky (US/Cannondale) +37secs
7. Geraint Thomas (GB/Team Sky) +39secs
8. Jon Izagirre (Spa/Movistar) +50secs
9. Tim Wellens (Bel/Lotto) +54secs
10. Gorka Izagirre (Spa/Movistar) +55secs
Final overall standings:
1. Richie Porte (Aus/Team Sky) 29 hours 10 minutes 41 seconds
2. Michal Kwiatkowski (Pol/Etixx - Quick-Step) +30secs
3. Simon Spilak (Slo/Katusha)
4. Rui Costa (Por/Lampre)
5. Geraint Thomas (GB/Team Sky) +41secs
6. Tony Gallopin (Fra/Lotto) +1min 03secs
7. Jakob Fuglsang (Den/Astana) +1min 05secs
8. Rafael Valls (Spa/Lampre) +1min 24secs
9. Gorka Izagirre (Spa/Movistar) +1min 38secs
10. Tim Wellens (Bel/Lotto) +2mins 18secs