The 49-year-old shared photos with co-stars Sean Murray (Timothy McGree), Brian Dietzen (Dr. Jimmy Palmer), Emily Wickersham (Eleanor Bishop) and Wilmer Valderrama (Nick Torres), sharing her love for them and the show.
"Finished shooting my last scene of NCIS with @SeanHMurray @BrianDietzen @EmilyWickersham @WValderrama Airs May 8th," Perrette wrote alongside the four photos. 'LOVE Y'ALL!!!"
Fans mourned the loss of Perrette's character, Abby Sciuto, and wondered why she wasn't sticking around until the show's finale episode on May 22.
"Thanks for 15 seasons of Abby! Gonna leave a big void. Can't believe Abby's leaving before the finale on May 22? Big blow to the team & fans," one person said.
"NCIS is never going to be the same without you :) You played one of my most favorite characters for the longest time and I fell in love with her punk adorableness :) I can't wait to see what's next for you and you will be tremendously missed," another fan wrote.
In a separate tweet shared Saturday, Perrette wrote that Abby's exit would come in two separate episodes.
"Abby's exit from #NCIS is in two parts. May 1 and May 8th. I worked really hard to give you my best. I really hope EVERYONE tunes in. Bless," she said.
Perrette announced in November that she would be exiting the CBS crime drama after the current season, having been a series regular and fan favorite since the very first episode in 2003.
In her exit announcement, she wrote that she made the decision in 2016 and denied rumors that she was starting a skincare line and that she was leaving due to problems with the show's creative team.
Because producers were aware of the star's departure from the beginning, George Schenck and Frank Cardea teased that the character will receive a "special send-off."
"We've known for some time this would be Pauley's final season on NCIS and have been working toward a special send-off," Schenck and Cardea told Deadline in October. "From day one, she has brought incredible passion and specificity to the role. Abby is a character that inspires millions of fans around the world, and all of us at NCIS are appreciative of Pauley for portraying her."