Charlesworth is the younger brother of Ben and has been part of the county's talent pathway for a number of years
Luke Charlesworth has signed a three-year rookie contract with Gloucestershire, bringing the number of sibling pairs in the first-team squad at Bristol to three.
Charlesworth is the younger brother of Ben, following in the footsteps of the Taylors, Jack and Matt, and the Prices, Tom and Ollie.
Luke, the latest of the six, has been part of the county's talent pathway for a number of years and made his second-team debut in 2019 when he was only 16.
He claimed five wickets in four second-team matches last year and will be part of the senior group's pre-season tour of Dubai.
"I'm delighted to be signing with Gloucestershire, it is such an amazing club that has helped me develop for a number of years already, so to receive the news was a real dream come true," he said. "I'm hugely grateful for the opportunity to grow as a cricketer and a person over the next three years.
"It has been really exciting to train with the lads and learn from top quality coaching staff. We have such a talented squad here and there's so much experience for me to feed off and advice to take on board."
Charlesworth's older brother, Ben, made his debut aged 17 (Jacques Feeney/Getty Images)
Charlesworth will train and play with the club, while continuing his studies at Exeter University, where he is in his first year as a student.
Tim Hancock, the club's head of talent pathway, added: "Luke is a fine young cricketer with plenty of potential. He is a player who can influence the outcome of matches, particularly with his bowling."
He is the second youngster to be awarded a rookie deal this winter, after Will Naish.