Curcumin is a phytochemical polyphenol extracted from turmeric rhizome, with multiple biological activities, intensively studied in various therapeutic areas. Its effects covers a wide range of specialties, from the neuroprotective to the antimetastatic properties, influencing pathologies from cardiovascular, neuronal and oncological fields, as a part of its broad spectrum of action. These effects are explained by antioxidant, anti-inflammatory and anticarcinogenic simultaneous roles of curcumin and its derivatives. In this review, we selected the information about morphological evidences correlated with the biological effects on the following organ systems: the central nervous system (including neurological pathology, such as Parkinson's and Alzheimer's disease), the cardiovascular system (including disorders like atherosclerosis, endothelial dysfunction and drug-induced myotoxicity), multiple forms of cancer, and metabolic syndromes including diabetes. The central point of this review was to target a variety of morphological changes at microscopic level induced by curcumin, using different microscopy techniques.