The 44 year old, with his son Jack on the bag, began the final round in 4th position and three shots from the then leader Julian Suri.
But, while Suri and several others succumbed to a difficult final round Gallagher rebounded from an 8 at the par 4 7th with six birdies to win by one over Masahiro Kawamura and by two over Spain’s Jorge Campillo.
Campillo produced the round of the day on day four (67) and after beginning the week as one of the pre-tournament favourites he so nearly justified that support.
As those behind him on the golf course were struggling, Campillo took the lead but the recovery of both Gallacher and Kawamura would see him finish alone in 3rd place.
Third-round leader, Suri, appeared in control of the tournament when he established a three-shot lead through 12 holes but a disastrous quadruple-bogey of his own at the 14th and the strong finish by others saw him finish tied for 4th.
For Australian Scott Hend, who was in contention for much of the week, however, it was a day to forget. Seven days earlier Hend had won the Maybank Championship but today it appeared he was running out of steam as he stumbled to a round of 79 and any chance of successive victories was gone.
Jake Higginbottom would finish as the leading Australian in a share of 27th place after a superb final round of 68, Hend would eventually finish in 35th place along with Marcus Fraser, Wade Ormsby was 39th and Sam Brazel 50th.
New Zealander Ben Campbell was 32nd.
For the winner, Gallagher, it was a day to remember especially with his son on the bag for their first win together.
“I am 45 this year so I am really proud of what I did out here today,” said Gallacher. “It changes my schedule and I can play a bit less and it was great to win with my son Jack on the bag.
“He has caddied for me 20 events already. It has been a great day. It was great to have him on the bag and Mother's Day as well makes it even more special."
The European Tour has a three-week break from tournaments on its own schedule although The Masters in two weeks is very much a European Tour event.
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