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The ability to sense Earth’s gravitational pull is essential for orientation, navigation, and proprioception in most organisms. Here, we demonstrate that C. elegans adults and dauers exhibit negative gravitaxis and that this behavior is modulated by other environmental inputs such as light and electromagnetic fields. We found that components of the DEG/ENaC pathway involved in gentle touch sensation – specifically the neuronally-enriched microtubule subunits MEC-7 and MEC-12, but not the related MEC-4 and MEC-10 mechanosensory subunits – are required for negative gravitaxis. In addition, we found that TRPA-1, a receptor protein associated with cold and mechanosensation in both mammals and invertebrates, is critical for this behavior. Finally, we show that PVD neurons, which utilize TRPA-1 to detect harsh cold, are also essential for gravity sensation. Conversely, TRNs are not required for this behavior. These findings implicate a complex, interconnected mechanism for gravity sensation involving an ion channel that is also present in the mammalian vestibular system.