Hilo does not rival Honolulu in terms of nightlife. It is far more low-key than Honolulu, but as Hawaii's second largest city and as home to a University of Hawaii campus, there is definitely nightife flourishing where the young and old intertwine*. Hawaiians love live music and karaoke is a favorite pastime as well, so finding either of these entertainments should be no problem.

The night  begins with watching the beautiful sunsets.  You can do that at Joji's Lounge which offers panoramic views, and--of course--delicious drinks. From there you can go in search of more action. At Ho'omalimali Lounge, you'll find a lot of it; the bar features great Hawaiian cocktails, live music, and karaoke. Other local favorite bars are the Flipside Too and Mina's, both located in the historic downtown center of Hilo.

If you want to catch a movie, see one at the historical Palace Theatre located downtown. Many of the hotels also offer live music and great bars; one particularly known for its music is the Nanilo Hotel and Resort which has a huge space for performing acts.

Always feel free to ask the locals and hotel and restaruant staffs where the happening places are for the night, they will be happy to help; it's the spirit of Aloha after all!

 

*should be "intermingle," but cute as is.