They will also have to undergo testing if they show Covid-related symptoms upon arrival or during a self-monitoring period.
They will also have to take precautions including, preferably, the use of masks.
Post-arrival random testing, however, will not be required for children under 12 years of age.
"All guests should preferably be fully vaccinated as per the approved primary schedule of vaccination against Covid-19 in their country,” Air India Express said in a tweet.
On November 7, the UAE lifted nearly all Covid-19 restrictions in the country after a steady decline in cases.
Only a small number of measures remain in place, including masks to be worn inside health facilities and hospitals.
The country is among the most thoroughly-vaccinated in the world and has conducted about 25 million PCR tests nationwide since the emergence of the coronavirus.
The guidelines are the first issued by an airline in the country since restrictions were removed earlier this year. Authorities began random Covid testing at various airports in response to increasing case numbers globally, particularly in neighbouring China.
Air India Express, which has its headquarters in the city of Kochi in the southern state of Kerala, flies to countries in West Asia and South-East Asia.
It is run by a fully-owned division of Air India, which was bought by the Tata group this year.
India has also made rapid Covid tests mandatory for international passengers coming from China, Japan, South Korea, Hong Kong, and Thailand as Covid case numbers continue to surge worldwide.
Those found to be symptomatic or test positive for Covid, will be put under quarantine.
A woman and her six-year-old daughter who returned from China via Colombo tested positive for Covid-19 on Wednesday. They had landed at Madurai airport in southern Tamil Nadu.
Their samples will be sent for genome sequencing.
India has reported at least four cases of the BF.7 sub-variant that has wreaked havoc in China, in at least two states.
The country reported a handful of Covid cases in recent weeks, with the health ministry on Wednesday reporting 157 cases and one death in the previous 24 hours.