Bol joined Oregon as a freshman in the 2018–19 season under head coach Dana Altman. Entering the season, he was considered one of the best prospects for the upcoming NBA draft, although analysts described him as a polarizing prospect in the long term. On November 6, 2018, Bol debuted with a double-double of 12 points, 12 rebounds, and 3 blocks in 23 minutes against Portland State. He later recorded a season-high 32 points and 11 rebounds in an 89–84 loss to Texas Southern. After recording 20 points, 9 rebounds, and 4 blocks in a 66–54 win over San Diego on December 12, Bol injured his left foot, which left him out of commission for the rest of the season. He declared for the NBA draft after his freshman season. Bol was projected as the third pick in the 2019 NBA Draft behind Zion Williamson and RJ Barrett before his season ending injury .