Most visitors to the Perhentians bypass the bulk of Terengganu and instead transit via Kota Bharu, in the neighboring state of Kelantan, which offers better connections by air and train and is only one hour away. However, Kuala Terengganu and other locations along the main north-south highway are accessible via long-distance bus from Kuala Lumpur, Penang and various other cities.
By plane
Kuala Terengganu's own Sultan Mahmud Airport TGG does field a number of flights daily from capital Kuala Lumpur and twice daily from Penang, as well as a thrice weekly international flight to Singapore by Firefly (http://www.fireflyz.com.my). It's a two-hour drive from here to Kuala Besut, the usual jumping-off point for the Perhentian Islands.
Alternative closest airport is KBR at Kota Bharu.