I do not think that a belief in God is necessary for a person to be moral. However, if this survey from Pew Research is to be believed, that puts me and many people in the richest countries in the world in a distinct minority from a global standpoint:
Many people around the world think it is necessary to believe in God to be a moral person, according to surveys in 40 countries by the Pew Research Center. However, this view is more common in poorer countries than in wealthier ones.
In 22 of the 40 countries surveyed, clear majorities say it is necessary to believe in God to be moral and have good values. This position is highly prevalent, if not universal, in Africa and the Middle East. At least three-quarters in all six countries surveyed in Africa say that faith in God is essential to morality. In the Middle East, roughly seven-in-ten or more agree in Egypt, Jordan, Turkey, the Palestinian territories, Tunisia and Lebanon. Across the two regions, only in Israel does a majority think it is not necessary to believe in God to be an upright person.
Many people in Asia and Latin America also link faith and morality. For example, Indonesians, Pakistanis, Filipinos and Malaysians almost unanimously think that belief in God is central to having good values. People in El Salvador, Brazil, Bolivia and Venezuela overwhelmingly agree. However, most Chinese take the opposite position – that it is not necessary to be a believer to be a moral person. And in Latin America, the Chileans and Argentines are divided.
The linked source has lot of interesting charts and graphs.
While I don’t think it’s necessary, I think that whether you believe in God or not it’s very difficult to be a moral person with the level of moral education that most Americans possess. Most of our moral educations are what we learned at our mothers’ knees. If that.
I don’t believe that moral conduct is natural to human beings (the Roman Catholic belief is that it’s natural but our present condition is unnatural) and it requires some work to gain an understanding of right conduct, work that most of us are unwilling to do.