Hugh John McDonald is an American musician who is best known for his session work and for being the current bass guitarist of American rock band Bon Jovi, which he joined as an unofficial member in November 1994, not becoming an official member until 2016. Before joining Bon Jovi, he was the bass guitarist for the David Bromberg Band, touring extensively worldwide and playing on many Bromberg albums. He has played with many other artists, both live and in the studio, and has recorded with Willie Nelson, Jon Bon Jovi, Richie Sambora, Steve Goodman, Ringo Starr, Lita Ford, Michael Bolton, Cher, Alice Cooper, Ricky Martin, Michael Bublé, Bret Michaels, others and did a few dates during Shania Twain's the Woman in Me TV tour.

He has worked with Bon Jovi in the studio since its inception and has been their bass guitarist since original bass guitarist Alec John Such's departure after Cross Road which was released in 1994, but was still regarded as an 'unofficial' member of Bon Jovi. At this time, McDonald was left out of most publicity shoots and album covers but did appear in some of the band's promo videos. The band members said they never agreed to officially replace Such. However, in 2016, McDonald was promoted to being an official member along with guitarist Phil X. Regardless, his work with the band earned him a 1995 Metal Edge Readers' Choice Award for "Best Bassist" (tying with White Zombie's Sean Yseult). McDonald was one of the studio musicians that recorded Bon Jovi's original first demo for the song "Runaway". When the song became a local hit, Jon Bon Jovi nevertheless assembled his band without McDonald. On the other hand he has also appeared on Jon Bon Jovi's solo album Destination Anywhere and was part of Jon Bon Jovi's backing group, The Big Dogs.

In 2018, McDonald was inducted into the Rock and Roll Hall of Fame as a member of Bon Jovi.