Loneliness is a distressing personal experience and a growing social issue. Social robots could alleviate the pain of loneliness, particularly for those who lack in-person interaction. This paper investigated how the effect of loneliness on anthropomorphizing social robots differs by robot appearances, and how it leads to the purchase intention of social robots. Participants viewed a video of one of the three robots(machine-like, animal-like, and human-like) moving and interacting with a human counterpart. The results revealed that when individuals were lonelier, the tendency to anthropomorphize human-like robots increased more than that of animal-like robots. The moderating effect remained significant after covariates were included. The increase in anthropomorphic tendency predicted the heightened purchase intent. The findings imply that human-like robots induce lonely individuals' desire to replenish the sense of connectedness from robots more than animal-like robots, and that anthropomorphic tendency reveals the potential of social robots as real-life companions of lonely individuals.