Nicholas or Nick Arnold may refer to:
Politicians Nicholas Arnold (lord justice) (1507–1580), English courtier and politician Nicholas Arnold (MP for Monmouthshire) (1600–1665)
Others Nick Arnold (writer) (born 1964), British writer of science books for children Nick Arnold (footballer) (born 1993), English association footballer Nicky Arnstein (1879–1965), alias Nick and Nicholas Arnold Edwin Nicholas Arnold (1940–2023), British herpetologist at the Natural History Museum, London