In many species, the allocation of exploration and exploitation responses to environmental stimuli is important for survival. In this exploratory study, we determined whether dogs (Canis familiaris) explored novel stimuli in a visual discrimination task using food reinforcers. Initially, the dogs were trained with two pairs of simultaneous visual discrimination tasks. Having achieved the learning criterion, the dogs were presented with a pair of stimuli including a novel stimulus and a previously reinforced stimulus in the probe trials (familiar stimulus). Dogs were reinforced by 50% for novel stimuli and 100% for familiar stimuli. The proportions of responses to novel and familiar stimuli in the probe trials were considered to reflect the propensity for exploration and exploitation, respectively. The five dogs tested selected the novel stimulus more frequently (in 22 of the 30 probe trials; binomial test, P = 0.016). Therefore, dogs prefer novel stimuli over familiar ones, suggesting that this species, which is less neophobic than wolves (Canis lupus), would likely allocate more responses to exploration. Comparisons among breeds or with wolves are warranted in future studies.