My background: Had been on F1 for 6 years until I changed to H1B on Oct.1 2014. I have been working for a company in NY city since March 2014.

I understand that I should file as resident for federal tax because I have been in US for more than 5 years, but I am very confused whether I should be considered as a resident for NYS tax.

According to the NY state website(Income tax definitions (http://www.tax.ny.gov/pit/file/pit_definitions.htm)).
You're a New York State resident for income tax purposes if:
Your domicile is New York State (see Exception below); or
Your domicile is not New York State but you maintain a permanent place
Of abode in New York State for more than 11 months of the year and
Spend 184days1 or more in New York State during the tax year.
Your domicile is:
The place you intend to have as your permanent home
Where your permanent home is located
The place you intend to return to after being away (as on vacation,
Business assignments, educational leave, or military assignment)

I don't think my domicile is NYS because I was on temp student visa (F1) and I
Was in NYS for my college education and practical training. My domicile should be my home country. In addition, I only rented an apartment for 10 months in New York in 2014 so I believe I should not be considered as a NYS resident.

I asked couple tax experts but none of them are very familiar with my situation.

Your status as an international student on a F-1 visa makes you, BY LAW, a NON-resident of NY state and New York City. You DO have to pay NY state income tax on income earned within the borders of NY state, but you are COMPLETELY EXEMPT from any NY City income taxes.

The NY state tax officials are not happy with this fact, but if you provide them with a copy of your F-1 visa, they will uphold your status as a non-resident.

Hi AtlantaTaxExpert,

Thank you for your reply. If I am not a resident of NY State, why do I have to pay NY state tax? Thank you.

Because you earned money while working WITHIN the NY state borders. Every state in the U.S. and every country in the world retains the right to tax the income that is earned while working within their country/state borders.