Van Hooijdonk made his Celtic debut on 11 January 1995 in a league match against Hearts at Hampden Park. The big striker made an instant impact for his new team by scoring a stunning opening goal. Hearts went on to equalise and the game finished 1–1. However, Van Hooijdonk settled quickly at Celtic and he became an instant favourite with the fans. When Van Hooijdonk arrived at Celtic they had not won any trophies in six years. However, with Van Hooijdonk Celtic won the Scottish Cup right away and Van Hooijdonk was the only goalscorer in the final against Airdrie in May 1995. The following season, 1995–96, saw Van Hooijdonk in outstanding form for Celtic. He scored 32 goals, including 26 in the League which saw him finish top scorer. Of particular note was Van Hooijdonk’s prowess at scoring from free kicks. However, despite Van Hooijdonk’s goals and the attractive football being played by manager Tommy Burns’ side, Celtic still finished the season without any silverware. Van Hooijdonk’s last season at Celtic, 1996–97, was an unhappy time for both the player and the club. A row with the Celtic chairman/owner, Fergus McCann, would rumble on through the year and as a result he often ended up on the substitute bench. The manager of the Dutch national team Guus Hiddink told him he would not be selected for the national team as long as he was not a regular first team player at Celtic.
In total Van Hooijdonk scored 52 goals for Celtic in 84 appearances. He eventually left Celtic over a wage dispute towards the end of the 1996–97 season, stating that the reputed £7,000 a week rise he was being offered might be “good enough for the homeless” to live on “but not for an international striker.” He went on to join Nottingham Forest in a deal worth up to £4.5 million.