The Spaniard had finished second six times since his win at the 2012 Dubai Desert Classic but overcame Callum Shinkwin in a play-off at Dundonald Links to win his third title.
Cabrera Bello posted a stunning course-record 64 to get to 13 under and a bogey from Shinkwin on the last meant the contest went to extra holes, where the 33 year old hit a stunning second into the 18th to set up a tournament-clinching birdie.
The Englishman had the consolation of securing his place at the Open Championship next week alongside Frenchman Matthieu Pavon, who finished third at ten under, and Australian Andrew Dodt who was two shots further back.
Day 4 highlights - AAM Scottish Open;
All the best of the action from the final day's play at Dundonald Links as the 2017 Aberdeen Asset Management Scottish Open came to a thrilling close.
Three-time Major Championship winner Padraig Harrington, New Zealander Ryan Fox, American Matt Kuchar and England's Anthony Wall were also at eight under.
"I'm extremely happy," said Cabrera Bello. "I've won before and I have been up there so many, many times with things not really working out for myself. I was starting to feel a little bit of pressure every time I was up there contending.
"I really felt I played some of the best golf of my life today. In the play-off, I really gave it a go and I'm extremely pleased it worked out for me. Winning again, it's an unbelievable feeling. I think I was overdue.
"I enjoy those pressure situations. I think they really define you."
I have really been fighting for this third win - Rafa Cabrera Bello;
Rafa Cabrera Bello shares his delight after a dramatic playoff victory in the Aberdeen Asset Management Scottish Open at Dundonald Links.
Dodt and Shinkwin began the day tied at nine under but Dodt soon jumped into a two-shot lead as he birdied the first after an excellent second from the heavy rough and put his tee-shot on the par three fourth to ten feet.
Cabrera Bello turned in 32 with birdies on the second, third, eighth and ninth as Shinkwin started with six pars but the 24 year old came to life from the seventh, putting two consecutive approaches to tap-in range to leapfrog Dodt - who had bogeyed the fifth - and take the lead.
Dodt had gone off the boil after that quick start but he put his second within eight feet on the eighth and cut the gap to one as the leading trio began to move away from the field.
There were nerves - Callum Shinkwin;
Callum Shinkwin reflects after losing out to Rafa Cabrera Bello in a play-off for the 2017 Aberdeen Asset Management Scottish Open.
Cabrera-Bello took advantage of the 14th to get within one as Dodt went bogey-birdie on the tenth and 11th but Shinkwin put his approach to two feet on the 13th to establish a cushion.
Dodt then three-putted the 12th and 13th to slip back and when Cabrera Bello put his approach to eight feet on the 17th, he was within one of the leader.
Shinkwin was showing absolutely no signs of nerves, however, and he put his tee-shot on the 15th inside ten feet for another birdie and once again he led by two.
Cabrera Bello got a lucky break to stay out of the water and make a birdie on the last to put the pressure on Shinkwin, with the leader hitting a poor chip and leaving his par putt short on the last to set up the play-off.
Five of the best AAM Scottish Open Day four;
The five best shots from the final day of the 2017 Aberdeen Asset Management Scottish Open at Dundonald Links.
Shinkwin had missed nine cuts in a row before making the weekend at the HNA Open de France two weeks ago but will no longer be worrying about his place on Tour after taking home a cheque for 777,770 dollars.
"It's been a very good week," he said. "End of the day, I'll be more than happy to finish second but the win was on my mind and didn't happen."
Pavon turned in 32 with birdies on the third, fifth, eighth and ninth and while he dropped a shot on the 13th, he bounced back with gains on the 14th, 17th and last.
Harrington bounced back from a 79 on Saturday with a 66, Kuchar and Wall signed for rounds of 69, Fox carded a 70 and Dodt got round in 73.
Englishmen Ian Poulter, Robert Rock, Lee Slattery and Andy Sullivan, Dane Søren Kjeldsen and American Rickie Fowler were then at seven under.
Blog credit to the European Tour.