The axial channelling behavior of boron implants in (lot)), (110) and (111) silicon wafers is investigated by secondary ion mass spectrometry. The conventional electronic stopping models are tested by comparing with experimental results. The dependence of the channelling effects on these three major low-index directiom are revealed. A three-parameter model is presented to describe channelling of boron in silicon. The results give a deeper insight into the channelling phenomena and provide the necessary information to study an electronic energy-loss model for boron Channelling in a silicon target.