I am happpily married with my husband for 15 years; without my knowledge my husband was envolved to this woman; not serious as what my husband claims and I honestly and truly believed him. The woman is from another country and she is currently working in Hongkong right now and she is demanding a financial support from my husband and continually harassing me for which I am very much affected emotionally and physically.

It helps to know what countries SHE is from, and you are from. Assuming you are not all from Hong Kong as the laws will vary country to country pertaining to support. It may change if he leaves Hong Kong. In any case... I'd demand DNA testing to prove her claims. Far too many women will latch on to a man with an income rather than the kids actual father. IF he ends up having to pay... at least he will know its really his and he isn't being scammed IF he remains in Hong Kong.

Since this was originally posted in a law forum (I moved it here from Immigration Law), I assume you want a legal answer.

Your husband's first move is to have a paternity test done to confirm whether the child is his. Once paternity has been established, then he can deal with the support issues.