The ventral tegmental area (VTA) encompassing dopaminergic (DA) neurons, is a brain region crucial for processing information about various rewards and guiding appetitive behaviours directed towards them. Importantly, how the VTA DA neurons encode different rewards and to what extent this information overlaps within different DA cells is poorly understood.For that reason, we recorded the electrophysiological activity of VTA neurons in freely-behaving male mice using silicon probes while the animals were free to spontaneously explore different rewards. The arena contained several natural rewards including water, food, a toy, a female conspecific and a running wheel.The activity of a majority of putative DA neurons was modulated by at least one reward. Despite the heterogeneity of responses, some patterns could be observed. For example, two subpopulations with different firing patterns were modulated by different types of rewards – one of them responded more strongly to the running wheel while the other to food. Encoding of speed in the running wheel and during free locomotion was uncorrelated, suggesting that voluntary exercise is represented differently in the VTA DA neurons than the spontaneous exploratory behaviour.Overall, our results show that the putative VTA DA neurons code different natural rewards heterogeneously. Some encoding patterns were present as, for example, we observed that separate subpopulations of DA neurons represent food and voluntary exercise. This suggests that VTA DA neurons are able to distinguish between different rewards, including the competing ones.Funding: ERC Consolidator Grant (772994, FeedHypNet, to TK) and DFG (SFB1451 and EXC2030-CECAD, to TK).