Analysis of synaptic events in the spinal dorsal horn arising from distinct, identified populations of sensory neurons is critical though technically complex. Sensory neuron populations in dorsal root ganglia are heterogeneous and have been grouped according to cell size, neuropeptide content, genetic markers, ionic current, and axonal conduction velocity. Conventional electrical stimulation methods are unable to selectively activate presynaptic fibers from specific subpopulations of neurons because sensory fibers comingle in the dorsal root. Here, we used optogenetic methods to elicit synaptic events in spinal cord slices and paw withdrawal responses in awake, behaving mice by activation of TRPV1-expressing or CaV3.2-expressing afferent fibers. We generated two mouse strains expressing a channelrhodopsin-YFP (ChR2-EYFP) fusion protein in either TRPV1- or CaV3.2-expressing neurons by mating existing TPRV1-cre mice (JAX #17769) and a new Cacna1h-cre strain generated by our lab to cre-dependent ChR2-EYFP-expressing mice (JAX #012569). CaV3.2-expressing neurons are characterized by large, low-threshold T-type currents, medium sized cell bodies, mechano-sensitivity, and a lack of capsaicin response. We found that the TRPV1-expressing fibers that detect noxious thermal stimuli terminate primarily in laminae I/II and colocalize with CGRP, as previously reported, whereas CaV3.2-expressing fibers terminate throughout superficial laminae of the dorsal horn and do not colocalize with CGRP. We recorded light-evoked, post-synaptic AMPAR and NMDAR currents in retrolabeled projection neurons and lamina II interneurons from TRPV1/ChR2-EYFP acute spinal cord slices. Additionally, an LED lamp applied to the ventral surface of the hindpaw elicited a nocifensive response in both TRPV1/ChR2-EYFP and CaV3.2/ChR2-EYFP mouse strains, but not in control mice. Using these strains, we can now activate specific subpopulations of sensory neurons and study the resulting synaptic currents in acute spinal cord slices and behavioral responses in awake, behaving mice.