A tractor-trailer fatally struck a retired La Guardia Community College librarian yesterday in Brooklyn.

Ngozi Agbim, 73, was crossing the nine-lane intersection at Church Avenue and the Prospect Expressway at 9:40 a.m. when the big rig turned to enter the expressway and ran her over with its rear tires.

The driver was issued a summons.

Agbim headed LaGuardia’s library and media services for 33 years.