AbstractWhile previous research suggests that individuals who humanize their companion animals may have insufficient human social support (Epley, Waytz, & Cacioppo, 2007), researchers have not examined the relation between companion-animal anthropomorphism and the health of animal guardians while taking into consideration their human social support levels. It was hypothesized that dog guardians with low levels of human social support would have poorer health if they engaged in high rather than low levels of anthropomorphism, while the health of dog guardians with high levels of human social support would not vary depending on their anthropomorphism levels. A sample of 203 Canadian dog guardians completed an online survey. Results revealed that, among dog guardians with low levels of human social support, those who engaged in high levels of anthropomorphism were more depressed, visited the doctor more often, and took more medications. Furthermore, among dog guardians with high levels of human social support, those who engaged in high levels of anthropomorphism were more stressed and depressed. These findings highlight the complexity of the relationship between anthropomorphic behavior, human social support, and dog guardians’ health.