Thank you for your answers and sorry for my late replay.

The following is my recipe:

250g cream cheese,
2 eggs (about 70g per egg),
90g sugar,
15g cron starch,
120g cream,
2tb lemon juice

The base is made of digestive biscuits and butter.

I think probably the reason is my metal model. It is a cheap one, so
probably the cake reacted with it and made itself became very eggy.

From your answers, I think maybe I made two mistakes in water bath:
First one is both water bath and corn starch are used. In a webpage
called "simple secrets to prefect cheesecake" ( http://goo.gl/je5uS ),
it is said "If your cheesecake batter has starch in the recipe (flour
or cornstarch), you do not need a water bath".

Second one is the fan in the oven was not used, while water bath is
used. I noticed there was a lot of steam in the oven. However, one fact
is strange. If the taste is caused by the steam, why only the edge of
the cake tastes eggy and the center is good?

Thank you again.
Xu