Before his departure from the colony, the New Zealand war broke out, and he immediately offered his services, which were accepted the same day, and he was appointed an extra member of Major-General (afterwards Sir) Thomas Pratt's staff. Three months later he was severely wounded by a bullet in the thigh, while in charge of the trenches, after laving out and constructing a parallel needed in the capture of the Kaihihi River pā—Mataiaio, Orongomaihangai and Pukekakariki. His wound proving serious, he became unfit for further duty, and returned to Melbourne invalided. For his services in New Zealand he was mentioned in despatches, and promoted to brevet-major, he having become captain soon after his arrival in Melbourne. Pasley also received the New Zealand Medal.