When many people think of Hawaiian beer, they erroneously think of Kona Brewing Company. The only problem with that, however, is that the majority of the beer from Kona Brewing Company is actually brewed on the mainland. If you're looking for beer that's brewed on Maui, the real microbrewery in Hawaii is Maui Brewing Company, located in the town of Kahana.
Since 2005, Maui Brewing Company has consistently been voted as the best craft brewery in Hawaii. While the beer itself is brewed in Lahaina, the popular brewpub is in the town of Kahana between the resorts of Kaʽanapali and Kapalua.
The great part about visiting the brewpub is that you'll find beers on tap that aren't available elsewhere. While popular beers such as Bikini Blonde, Big Swell IPA, and Coconut Porter can be found in restaurants (and markets) across the island, other beers such as the Pau Hana Pilsner and Pueo Pale Ale can only be found at the brewery.
If you're into dark beers, it's one of the only places on the island where you can get a proper stout.