Coordinated multi-joint limb and digit movements - "manual dexterity" - underlie both specialized skills (e.g., playing the piano) and more mundane tasks (e.g., tying shoelaces). Impairments in dexterous skill cause significant disability, as occurs with motor cortical injury, Parkinson's Disease, and a range of other pathologies. Clinical observations, as well as basic investigations, suggest that cortico-striatal circuits play a critical role in learning and performing dexterous skills. Furthermore, dopaminergic signaling in these regions is implicated in synaptic plasticity and motor learning. Nonetheless, the role of striatal dopamine signaling in skilled motor learning remains poorly understood. Here, we use fiber photometry paired with a genetically encoded dopamine sensor to investigate striatal dopamine release in both male and female mice as they learn and perform a skilled reaching task. Dopamine rapidly increases during a skilled reach and peaks near pellet consumption. In dorsolateral striatum, dopamine dynamics are faster than in dorsomedial and ventral striatum. Across training, as reaching performance improves, dopamine signaling shifts from pellet consumption to cues that predict pellet availability, particularly in medial and ventral areas of striatum. Furthermore, performance prediction errors are present across the striatum, with reduced dopamine release after an unsuccessful reach. These findings show that dopamine dynamics during skilled motor behaviors change with learning and are differentially regulated across striatal subregions.Significance Statement Dexterity is central to everyday life but impaired in Parkinson's Disease, which is characterized by midbrain dopamine neuron degeneration. These neurons project to the striatum, where dopamine release plays a role in motor learning and execution. Endogenous dopamine dynamics in striatal subregions and how they relate to dexterous skill remain unclear. We used a fluorescence-based dopamine biosensor to elucidate the pattern of dopamine release in striatal subregions as mice learn and execute single pellet skilled reaching. Dopamine release varies across dorsolateral, dorsomedial, and ventral striatum as mice learn the task, and demonstrates 'performance prediction errors' when mice fail to retrieve the pellet. These results suggest that phasic dopamine dynamics are important for learning and executing dexterous skills.