The Spaniard edged an exciting sprint finish, which saw the peloton swallow him and fellow breakaway rider Dan Martin in the dying stages.
Martin slipped to fifth but Valverde refused to be beaten, climbing out of the saddle and sneaking across the line in first. Colombia’s Jarlinson Pantano and France’s Arthur Vichot took second and third respectively.
It was a Spanish 1-2-3 in the overall standings as the 2009 champion was followed by Alberto Contador and Marc Soler, who were 1:03 and 1:16 adrift. Great Britain’s Adam Yates placed fourth.
"Today I felt good after a really hard stage yesterday, everything was easier today because of the team," Valverde told reporters.
"I knew Daniel (Martin) would attack when he did as he always does that and I worked very hard to stay with him and in the end I won by a hair's breadth."
Chris Froome, whose overall title hopes were extinguished on Saturday, looked set to take the final stage with a brave solo attack, but he was overhauled by the pack with five kilometres remaining.
There was minor consolation for the Brit, however, as he took second spot in the mountains classification behind Valverde.
Stage seven results
1. Alejandro Valverde (Spain / Movistar) 3:08:49"
2. Jarlinson Pantano (Colombia / Trek) ST
3. Arthur Vichot (France / FDJ)
4. Rafal Majka (Poland / BORA)
5. Daniel Martin (Ireland / Quick-Step)
6. Aldemar Reyes (Colombia / Manzana Postobon)
7. Romain Bardet (France / AG2R)
8. Davide Formolo (Italy / Cannondale)
9. George Bennett (New Zealand / LottoNL)
10. Steven Kruijswijk (Netherlands / LottoNL)
1. Alejandro Valverde (Spain / Movistar) 25:27:15"
2. Alberto Contador (Spain / Trek) +1:03"
3. Marc Soler (Spain / Movistar) +1:16"
4. Adam Yates (Britain / Orica) +1:31"
5. Tejay van Garderen (U.S. / BMC Racing) +1:34"
6. Daniel Martin (Ireland / Quick-Step) +2:29"
7. Steven Kruijswijk (Netherlands / LottoNL) +2:56"
8. Carlos Verona (Spain / Orica) +3:00"
9. George Bennett (New Zealand / LottoNL) +3:01"
10. Romain Bardet (France / AG2R) +3:05"
Read the original article on Eurosport: Valverde caps Catalunya title with final stage success