The Spanish forward, who scored his last hat-trick for former club Tenerife, continued his fine form in the 3-1 win over Southampton.
Newcastle made a strong start at St James' Park but Miguel Almiron was unable to beat Angus Gunn from a tight angle inside the first 10 minutes.
The home fans did not have too long to wait for the first goal. Perez picked up possession in the middle of the park before running towards goal and he was able to round Maya Yoshida before finding the bottom corner.
He made it 2-0 in the 31st minute after Southampton were punished for giving the ball away. Salomon Rondon charged down the left wing before cutting the ball back and Perez was on hand to slide in at the back post before tapping home.
Ralph Hassenhuttl's men made a good response in the second half and they put pressure on the home side when they found a way through in the 59th minute. Substitute Mario Lemina worked a one-two on the edge of the box with fellow sub Stuart Armstrong before he opened his body to curl a shot into the far corner.
After a few nervous moments, Newcastle then hit the post as Ki Sung-Yong tried his luck from the edge of the box. Isaac Hayden was then denied by a stunning save from Gunn, while Yoshida went close at the other end after heading over Nathan Redmond's cross.
In the 86th minute, Southampton cleared two headers - from Mo Diame and Rondon - off the line but just seconds later the hosts killed the game off as Perez celebrated his hat-trick.
Matt Ritchie's diving header looked like it was going in and Perez's flick made sure as he lapped up the applause from the home crowd.
In stoppage time Southampton were denied again as Yoshida's header was tipped wide by Martin Dubravka and that allowed Newcastle to celebrate another superb win after confirming their place in the top flight for next season.