Having defeated second seed Gael Monfils in the semi-finals, Kyrgios wrapped up his third title of 2016 following victories in Atlanta and Marseille, triumphing 4-6 6-3 7-5 over Coffin in Tokyo.
It was a dramatic two-hour encounter as both players struggled to capitalise on break-point opportunities that came their way before the Australian forced the only break of the decider to move 6-5 ahead and successfully served out the match.
The 21-year-old will hope the biggest title win of his enigmatic career to date is a sign of things to come and will be particularly pleased with the manner in which he kept fighting until the end.
Goffin passed on three set points in the opener before finally edging ahead. However, the world number 14 was left to rue a missed opportunity in the third game of the second set when Kyrgios survived five break point chances.
Kyrgios, who hammered down 25 aces, held firm and immediately broke the Belgian to pave the way for a decider that the prodigious young Australian edged.