Mrs.Toh,

I am afraid that you can’t check in your luggage at Tsim Sha Tsui MTR Station. If you use airport express service, you can check in your luggage at Hong Kong and Kowloon Station. But I check its website and didn’t find your airline on that page. You may contact your airline for details.

Here is the page: http://www.mtr.com.hk/eng/airport_express/complom_checkin.html