The aim of this study was to optimize the extraction and characterization of lycopene, a carotenoid, from a tropical fruit, Psidium guajava L. and to demonstrate its health benefits. Deionised water, mixed with organic solvents, was used for extraction, and the depletion stage was reached in order to define the number of extractions needed to extract most of the lycopene. Optimum extraction was achieved with petroleum ether combined with guava puree:deionised water ratio of 40% using 15 ml of water. Four extractions were a satisfactory compromise to maximize the amount of lycopene recovered and to minimize the use of organic solvent. Excellent purification of lycopene was obtained by HPLC-VIS detection (470 nm) with acetonitrile/methanol/tetrahydrofuran mobile phase. Characterization was confirmed by FTIR analysis. A modification of the DPPH test made it possible to assess the EC50, thereby ranking lycopene among good antioxidants. As Psidium guajava is already widely used in the food industry, these results support claims for health benefits for products derived from guava.