The airline on Thursday released a picture showing the 86-seat aircraft, named Nok Anna, taking off from the Canadian aircraft maker's Toronto facilities.
The delivery followed Nok Air's move last month to convert two of the four previously placed options for such aircraft into firm orders.
The conversion, valued at US$66 million, raised Nok Air's total commitment to six.
The move reflects Nok Air's strategy to further consolidate its secondary route network, which has seen a vacuum following a break-up earlier this year with Siam General Aviation (SGA).
SGA has ceased operating on March 30 after serving a "letter of termination" to Nok Air to suspend charter services on secondary routes for the budget airline, and grounding all of its six Saab 340B turboprops, each with 34 seats, which served those low-density routes, mostly domestic.
Nok Air executives said the Q400s will not only play a major role in the airline's domestic development, but also in the international expansion.
The SET-listed airline is looking at new destinations such as Myanmar, Laos and Cambodia — areas with airports not serviceable by jets but accessible with the Q400 turboprop.
Nok Air is expected to have a total fleet of four Q400s by the end of 2014, with the two additional orders joining the fleet in 2015.
The Q400s will essentially replace two ageing ATR-72 turboprops it leased from Thai Airways International.
NOK shares last traded on the Stock Exchange of Thailand at 16.20 baht, unchanged, in trade worth 12.8 million baht.