Bruce Gomola Jr., of Burlington Township, was charged with first-degree murder, two counts of aggravated assault and possession of a weapon for an unlawful purpose.
Gomola is employed as a corrections officer at the Burlington County Jail in Mount Holly, investigators said.
The Burlington County Prosecutor's Office said the shooting occurred at the Delaware Valley Urology office on the 1500 block of Midlantic Drive, near the Mount Laurel Police Department.
Officials said Gomola apparently became upset concerning an appointment for his father.
Stephanie Horton, a patient services representative at the office, attempted to discuss the situation with him.
That's when the prosecutor's office said Gomola pulled a .40 caliber handgun and shot Horton in the chest.
The same bullet then struck a female patient in the knee.
Horton, 44, of Willingboro, was taken to Cooper University Hospital in Camden where she was pronounced dead.
The injured patient, described as a woman in her 50s, was treated at the hospital for non-life-threatening injuries.
After the shooting, according to the prosecutor's office, Gomola left the office building and drove away. He returned to the scene soon after and surrendered to a Mount Laurel detective.
Gomola is being held in the Camden County Correctional Facility.