The heterotrimeric G protein Gq positively regulates neuronal activity and synaptic transmission. Previously, the Rho guanine nucleotide exchange factor Trio was identified as a direct effector of Gq that acts in parallel to the canonical Gq effector phospholipase C. Here we examine how Trio and Rho act to stimulate neuronal activity downstream of Gq in the nematode Caenorhabditis elegans. Through two forward genetic screens, we identify the cation channel NCA-1/NALCN as a downstream target of the Gq/Rho pathway. By performing genetic epistasis analysis using dominant activating mutations and recessive loss-of-function mutations in the members of this pathway, we show that NCA-1 acts downstream of Gq in a linear pathway. Through cell-specific rescue experiments, we show that function of this channel in head acetylcholine neurons is sufficient for normal locomotion in C. elegans. Our results suggest that NCA-1 is a physiologically relevant target of neuronal Gq/Rho signaling in C. elegans.