Cow's milk allergy (CMA) is an increasingly common problem among children and adults that requires the use of appropriate diagnostics to eliminate allergic reactions and prevent unnecessary dietary regimes. The current diagnostics methods are imperfect hence new, more effective methods are still being sought. Component-resolved diagnostics (CRD) is one of them. CRD assesses sensitivity to individual allergen molecules using purified native or recombinant allergens. The present paper reviews the role of CRD in diagnosing CMA, as well as the benefits and limitations of its use, especially in predicting allergy development or acquiring immunotolerance. It examines the possibility of replacing the current gold diagnostic standard with component tests directed against specific milk proteins. In addition, CRD could be helpful in the evaluation of prognosis. However, CRD allows for improvement in clinical management, particularly of polysensitized subjects, there is still no cogent evidence that it offers more efficient CMA diagnostics than existing tests.