score:4
Amex is well accepted in HK. There are some places that don't take it, but they're not that frequent, and usually mom and pop stores. Having a little cash (or an Octopus card with a few hundred HKD on it) will help, if you only have Amex.
Upvote:1
I would suggest you to prepare Visa / MasterCard as well.
From my general perception, AMEX is accepted in bigger merchants only.
Visa / MasterCard is well accepted around the city, including almost all restaurants & shops in malls.
Also, it is also good to know that Octopus card is also well accepted for smaller amount transactions, including transportation, convenient stores, supermarkets, etc.
Finally, some smaller merchants accept cash only.
(Hongkonger)