Microalgae comprise photosynthetic microorganisms with relatively simple nutritional requirements, which produce substances of interest for the food industry, in the biofuel area and for pharmacological purposes. From a biotechnological point of view, microalgae are a group that has not yet been studied and represent a promising natural resource and a great opportunity for new discoveries. This was the first study to evaluate the production of phycocyanin and protein by the microalgae Synechococcus nidulans LEB 115 recently isolated by the Laboratory Group of Biochemical Engineering using white light emitting diode (LED) lights in different photoperiods. Phycocyanin is a protein-pigment complex that may be used as a dye in food, cosmetics and in diagnostic tests in medicine. The aim of this research was to evaluate the production of phycocyanin and protein by Synechococcus nidulans LEB 115 cultivated with white LEDs varying the photoperiod. Two trials were performed, one with full-time photoperiod (continuous light) and the other with partial photoperiod (12h light: 12h dark). The culture medium used was Zarrouk and the initial concentration of the inoculums was 0.2 g L-1. The period with light was provided by white LEDs. The levels of phycocyanin and proteins were determined in the lyophilized microalgae biomass. All analyses and experiments were performed in triplicate. As a result, S. nidulans LEB 115 showed no difference in the biomass concentration with the variation in the photoperiod. However, it presented a higher concentration of phycocyanin (38.96±0.83 mg g-1) when grown in a full-time photoperiod. The protein content did not differ significantly either, from 52.90±0.16 g 100g-1 in the partial culture and 51.86±0.78 g 100g-1 in the full-time culture. All in all, due to the increase of periodicity of light through white LEDs, a higher production of biocomposites may be added, in this case, phycocyanin.