The neon liquid-vapor interface was studied at the triple point by path-integral Monte Carlo simulation with a view to determining the magnitude of quantum effects. Comparison is made between classical and quantum descriptions. The quantum interface is found to be approximately one quarter of an interatomic spacing wider than the classical counterpart. The surface tension is 20% lower than that obtained classically. Kinetic energy density profiles through the interface show anisotropy between the x and z directions. Marked differences are also found between the zero-pressure densities of the quantum and classical bulk liquid phases. © 1989 The American Physical Society.