The team held a news conference Wednesday at Barclays Center, its new home for the coming season, to introduce Hopkins.
"Walt's a genius. He has this humble confidence about him," Liberty general manager Jonathan Kolb said. "He's a person of character. He's a person of high basketball intellect. He's an elite level communicator."
Hopkins has been an assistant for the Lynx for since 2017.
The 34-year-old coach is excited for the bright future the Liberty have on and off the court and said that was a big reason why he decided to take the job.
"The ownership, the No. 1 pick, the new arena, the move to Brooklyn, all of it are factors," Hopkins said. "Had this team been in Westchester with this ownership, I still would have jumped at it. Those are icing on the cake. Things that are really nice, I didn't need to hem to help make the decision; it was more about the people."
Former Liberty coach Katie Smith's contract wasn't renewed after the season ended in September.
The team has the first pick in the WNBA draft in April and most likely will select Oregon guard Sabrina Ionescu.
This is the first coaching hire for the Liberty under owner Joe Tsai's group, which bought the team last year. Tsai also owns the Brooklyn Nets.
Before his time at Minnesota, Hopkins was the academic coach at Cal. He previously was director of basketball operations and player development for the Tulsa Shock.
ESPN's Mechelle Voepel and The Associated Press contributed to this report.