Morris Hatalsky, Bruce Fleisher and Dave Eichelberger shared second at 7-under-par 209.
After he fired a 7-under 65 to take the opening-round lead on Friday, Mason cooled down with a 1-over 73 to fall two shots off the lead Saturday. The spark returned during the final round as Mason played well at Upper Montclair Country Club on his way to victory.
'I knew if I shot somewhere in the 60s today I'd have a chance,' said Mason. 'Everything came together this week.'
At the par-4 second, Mason knocked a wedge onto the green from 105 yards and watched as the ball spun back towards the cup and fell in for an eagle. He followed that shot with a birdie at the third to reach 9-under.
'Lady Luck was smiling on me on the front nine,' said Mason.
Mason bogeyed the fifth but responded at the very next hole. He found a greenside bunker with his approach but blasted out of the sand for a birdie.
He dropped a shot at the 10th but picked it back up with a 20-foot birdie at the 11th. At the 12th, Mason hit his second shot within three feet of the cup and grabbed a two-shot lead over second-round co-leader Jay Sigel.
The lead increased to three as Sigel bogeyed the 12th and Mason solidly held on to the margin.
Mason fell back to 9-under with a bogey at the 16th as Eichelberger moved within one shot of the lead. However, Eichelberger's bid was soon silenced as the 58-year-old bogeyed the 17th.
'I played with Mason yesterday,' said Eichelberger. 'He was nervous starting out but managed to hold it together. I guarantee you his heart was pumping out there today.'
Mason hit an errant drive at the par-5 last but recovered from the rough with a shot that landed in the middle of the fairway.
He sent his third shot over the fountain in front of the green and landed the ball within 12 feet of the hole. The 51-year-old teaching pro from Georgia hit his first putt short but tapped in for par and the win.
With the victory, Mason earned a one-year exemption on the Senior Tour.
'I don't need to go to Monday qualifying anymore,' said Mason. 'To do this is phenomenal. It really hasn't sunk in yet.'
Sigel, who was attempting to win for the second straight week, struggled to a 2-over 74 to finish three shots off the lead. He was joined by Walter Hall, the last first-time winner on tour, at 6-under-par 210.
Former quarterback Steve Bartkowski shot a 6-over 78 to win the NFL players' portion of the event. San Diego tight end David Binn was second at 81, followed by former Denver star John Elway at 82.
Bartkowski donated his $34,000 top prize to the Brain Tumor Foundation for Children.
Final results from the NFL Golf Classic