The system was restored by 10:30 a.m. but the airline warned that delays will persist throughout the day. As of 11 a.m., there were 40 delayed flights, according to JetBlue.
At New York's John F. Kennedy International Airport - JetBlue's largest base of operations - about a third of all the airline's flights were listed as "delayed" on the flight monitors. The typical delay was about 90 minutes.
The airline blamed "IT network connectivity issues" but did not elaborate.
Computers are used to calculate weight, fuel and other key information needed before a plane can leave the gate.