Westerleigh is located in the northwest quadrant of the borough and is bounded in the east by Manor Road, the west by the Martin Luther King Jr. Expressway (New York State Route 440), the south by Victory Boulevard and to the north by Forest Avenue.

Westerleigh occupies high ground on Staten Island. While not as high as Todt Hill (the city's tallest point), from certain vantage points Westerleigh affords views of Newark, New Jersey, and farther afield on a clear day. The neighborhood has an abundance of coniferous and deciduous trees; including acacia, blue spruce, cedar, chestnut, elm, honey locust, paulownia, pin and royal oak, sweet gum, sycamore, tulip poplar, yew and many types of pine, some of which reach 75 feet (23 m) or more in height. On the neighborhood's southern side near the Staten Island Expressway is Ingram Woods, a remnant of a larger forest that has been preserved as an undeveloped park.