How much is a round trip Airport Express ticket in Hong Kong? Is it only for tourist?

The fare to/from HK Station is HKD180. It is HKD160 to/from Kowloon Station, HKD110 to/from Tsing Yi station.

It is not only for tourists. All people who wanna use AE can buy the ticket. And the HK AE Travel Pass is is restricted to tourists (non residents in HK) who have been there for less than 14 days at the time of purchase.