The midfielder has surpassed the Real Madrid icon's tally of 79 European victories following his side's 3-1 triumph over AC Milan at Camp Nou
The 33-year-old leapfrogged his fellow countryman due to his appearance in the Catalans' 3-1 win over AC Milan on Wednesday, a game which ended as his 80th victorious outing in the competition.
Lionel Messi scored from the penalty spot before Sergio Busquets doubled the hosts' lead, though Massimiliano Allegri's men were offered a lifeline from a Gerard Pique own-goal.
However, the Rossoneri failed the seize their chance to secure an unlikely result and Messi added a second goal to ensure the Blaugrana finished with a two-goal cushion.
Xavi was captaining the side in Carles Puyol's absence, playing in his 141st match (including qualification matches) in the elite European competition.
The victory guarantees a spot in the last 16 for the Catalans as no two of Celtic, Milan and Ajax cannot overtake Gerardo Martino's men.
Fellow Liga giants Atletico Madrid also sealed their place in the knock-out stages with a victory over Austria Vienna on Wednesday, while Real Madrid are expected to make it into the tournament's last 16 in the fifth group-stage fixture later in November.