Terry, 31, will arrive at Westminster Magistrates Court on Thursday to answer a charge of using racist language against QPR defender Anton Ferdinand, an accusation the player denies.
The centre-back has continued to play for his club since the charge was brought in December, but his manager admits he is prepared to give the player time off if it is needed in order to prove his innocence.
However, the Portuguese is hopeful that will not be necessary. "Eventually, if it is important for the justice, we will do it," Villas-Boas said, when asked about the possibility of giving Terry a leave of absence.
However, he added: "You have seen with the off-field events, we haven't stopped using John, and his level of performance has not been affected. If that continues to be the case, we will continue to do it."
Terry came up against Ferdinand for the first time since the alleged incident at the weekend, as Chelsea beat QPR in a controversial FA Cup fourth round tie at Loftus Road.
The England skipper was the subject of abuse from the stands for much of the match, but Villas-Boas praised his ability to ignore the distraction and put in a solid performance.
"He is a player that has been through various situations, situations of stress and great, difficult atmospheres," he added. "Bearing in mind the events that have happened in the past, he showed that this was just another game for him and he was just interested in football. He had an extremely good performance."
Chelsea return to Premier League action on Tuesday, as they travel to Swansea looking to cut the gap on third-placed Tottenham.