The budget carrier, a joint venture between Indonesian Lion Air and Malaysia's National Aerospace and Defense Industries, will offer daily services using Boeing 737-800 aircraft.
The hybrid carrier faces competition from SriLankan Airlines which operates double-daily service, Malaysia Airlines with 11 weekly flights and AirAsia with daily flights.
Flights depart Kuala Lumpur's klia2 terminal at 22:00 local time arriving in Colombo at 23:55. The return flight departs Sri Lanka at 23:55, getting back to the Malaysian capital at 06:15. The flight between Kuala Lumpur and Colombo will take three hours 25 minutes.