Collagen is widely used in the cosmetics industry as an active ingredient in skin-care formulations due to its biocompatibility, biodegradability, low antigenicity, and high biological activity. As a natural humectant, collagen binds water molecules within the skin, reduces transepidermal water loss, and helps maintain skin elasticity and hydration. Despite its broad application, the influence of collagen on epithelial ion transport remains insufficiently understood. This study evaluated the effect of a gel containing triple-helical collagen on sodium and chloride ion transport in the isolated rabbit skin. The collagen gel was applied to 25 skin specimens for 24 h and compared with 30 untreated control specimens. Electrophysiological analyses included measurements of transepithelial electrical potential (PD), electrical resistance (R), and potential changes during stimulation (PDmin and PDmax). Collagen gel significantly decreased R compared with control tissues, indicating altered tissue permeability. Collagen gel-treated tissues also exhibited a significantly more electropositive PDmin than controls, whereas PDmax values remained comparable between groups, suggesting that electrophysiological responsiveness was maintained under the experimental conditions. The observed electropositive shift in PDmin may reflect altered sodium ion transport. Whether these electrophysiological changes are associated with changes in tissue hydration requires direct investigation.