The pair landed in court after an Emirati woman complained about the public kiss, which the couple insisted was just a peck on the cheek. They were arrested in November and convicted of inappropriate behavior and illegal drinking.
Cosmopolitan Dubai has the most relaxed social codes in the conservative Gulf, but authorities enforce strict decency laws and regularly crack down on people accused of pushing the limits, which can include everything from wearing a mini skirt to losing one's temper in traffic.
As recently as Sunday, though, a young Italian-Iranian couple could be seen kissing among the visitors to the 127th floor observation deck of the Burj Khalifa, the world's tallest skyscraper.
Last month an Indian couple was sentenced to three months in jail for exchanging steamy text messages. In 2008, two Britons accused of having sex on the beach got three months in jail, though their sentences were later suspended.
Ayman Najafi and Charlotte Adams - both in their 20s - were arrested after an Emirati woman claimed they exchanged a passionate kiss in a restaurant where she and her daughter were having dinner.
Najafi and Adams attended Sunday's hearing, but did not speak. Their lawyer, Khalaf al-Hosany, told the court in a previous hearing that they kissed on the cheek as a greeting and "never intended to break the law."
Appeals court judge Iysar Fouad upheld the conviction, the jail time and a fine of 1,000 dirhams - about $270 - each. They will be deported after serving their sentences.
The couple has 30 days to appeal Sunday's ruling in a higher court.
Their lawyer said Najafi and Adams were not in a relationship, but knew each other before they met in Dubai.
Najafi worked for a marketing firm in Dubai and Adams was visiting the Muslim city-state with a Western outlook that has become famous for its beaches, ever-taller skyscrapers and anything-goes attitude.