The rat's prefrontal cortex plays a role in integration of feeding-related information. In this study, we investigated the neuronal activity changes of medial prefrontal cortex during licking of sucrose solution by freely moving rats. We found two different types of excitatory and two different types of inhibitory single neuron responses time locked to the beginning of the licking clusters. Changes in firing rates occurred either within 2 s before the first lick of the licking cluster or during the licking cluster. These observations suggest that neuronal responses in the medial prefrontal cortex may represent anticipation and consummation of liquid food reward.