He defeated incumbent MLA Ernest Bernhardt to win the Kitikmeot electoral district.
Ng served one term in the Northwest Territories Legislature, becoming a cabinet Minister in the government.
Ng ran for a seat to the Legislative Assembly of Nunavut in the first general election held in 1999.
Ng won the Cambridge Bay electoral district, and was appointed to the cabinet as the first Minister of Finance for the territory.
He served one term before retiring in 2004 at the dissolution of the legislature to devote more time to his family.