Although only 10 races into the current campaign, team principal Peter Sauber sees no reason to replace Japanese Kobayashi and Mexican rookie Perez.
Both drivers have had good results this season, scoring 35 points for the Swiss team, who lie sixth in the constructors' championship.
Kobayashi has earned 27, finishing fifth in Monaco, while Perez's highlight of the season so far was coming seventh at Silverstone earlier this month.
"I'm very proud and want to thank the team for keeping their faith in me," said 24-year-old Kobayashi.
Mexican Perez, 21, said: "Of course it is very good to have continuity and this way I can intensively prepare with my race engineer for what will be my second season."
Both drivers will be racing in the Hungarian Grand Prix this weekend at the Hungaroring.