Scotland international Lamont has signed a new two-year deal, which will keep him at Scotstoun until at least the summer of 2016.
Hughes has signed a one-year professional contract, after spending the last season at Scotstoun as a Scottish Rugby Elite Development player.
Lamont and Hughes become the latest players to commit their future to Glasgow and have given the club a massive boost ahead the RaboDirect PRO12 Final with Leinster on Saturday.
33-year-old Lamont re-joined the Warriors in 2012, having played for the club between 2003 and 2005.
The former Northampton Saints and Scarlets back, who can play on the wing or at centre, has made 68 appearances and has scored 120 points for the club over his two spells in Glasgow.
He has gone on to win 86 caps for Scotland over the last 10 years and has scored 60 points for his country.
Sean Lamont said: "It was fantastic to be able to come back to Glasgow in 2012 and I'm delighted to be staying here for at least another two years.
"I'm now one of the oldest players at the club, but I feel good and I want to continue to play at the highest level for as long as possible.
"I'm happy in Glasgow and I'm proud to be playing for this club.
"We've had a good season so far but we're not finished yet. We're all really looking forward to our first RaboDirect PRO12 final this weekend."
21-year-old Hughes made his debut for the club in the win over Connacht at Scotstoun in February and has gone on to make three appearances for the RaboDirect PRO12 finalists.
He was part of the Warriors squad which won the the Melrose 7s last month.
Rory Hughes said: "I've learnt a lot this season and I'm really happy to be staying at the club.
"This is a big opportunity for me and I'm determined to make the most of it."
Glasgow Warriors head coach Gregor Townsend said: "This will give everyone at the club and our supporters a boost ahead of the final with Leinster on Saturday.
"Sean (Lamont) has worked hard this season and is in great physical shape.
"He has played in four different positions in the backline for us and has performed at a consistently high level.
"Rory (Hughes) is strong, quick and has made a number of technical improvements this season. The work he has put in has been transferred into much more control and discipline in his game. It's great news that he's going to continue his development at Scotstoun.
"This season Rory gained an understanding of what is required at pro level and he also played very well at the Melrose 7s. His hard work led him to being our top try scorer on the day.
"We are delighted that both Sean and Rory are staying at the club."
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