Neuropeptide Y (NPY) family peptides, such as NPY and peptide tyrosine-tyrosine (PYY), are well known to regulate feeding behavior via cognate receptors expressed throughout the gastrointestinal tract and central nervous system. Interestingly, both NPY family peptides and receptors are also expressed in taste bud cells (TBCs) of the peripheral gustatory system. These cells of the lingual epithelium are the primary sensory cells of the gustatory system responsible for the detection of sapid chemical stimuli (characterized as “sweet”, “sour”, “bitter”, etc.) strongly related to the consumption of foodstuffs. Previous studies have indicated that NPY family peptide signaling can impact upon taste-related behaviors in mice, possibly modulating taste responsiveness and food intake as a function of metabolic state. Yet, it remains unclear whether these impacts are specifically mediated by modulation of the response properties of TBCs or by the influence of NPY family peptide signaling on the functioning of other tissues. The experiments described in this dissertation interrogated the role of NPY family peptides in the modulation of stimulus-evoked taste responsiveness at the cellular and behavioral levels. The functional responsiveness of human and mouse TBCs to prototypical taste stimuli, in the presence and absence of NPY and PYY, was assessed in vitro using calcium imaging and neurotransmitter release measurements. Behavioral responsiveness was measured by brief-access taste testing in mice, with and without oral exposure to NPY and PYY. These studies revealed that both NPY and PYY can modulate cellular and behavioral responsiveness to prototypical taste stimuli. The nature of modulation depended on the peptide and taste quality assessed. Both NPY and PYY enhanced responsiveness to fatty acid stimuli while bitter responsiveness of human TBCs in vitro was suppressed by PYY but enhanced by NPY, though both peptides reduced bitter avoidance in mice. These data suggest that peripheral taste function can be differentially modulated by NPY family peptides. Given the importance of gustation to food choice and intake, the results detailed are consistent with the broader theory that peptidergic signaling in TBCs can shape gustatory sensory information to potentially modulate feeding behavior in different metabolic contexts.