The focus of study is the investigation of growth rate, chlorophyll a content and lipid accumulation of microalgae chlorella sp. under the white light spectral conversion by a natural pigments, phycocyanin. For this purpose, in front side layer of a two-layer photobioreactor microalgae chlorella sp. was cultivated and rear layer was filled with phycocyanin solution (main sample). The results were compared with control reactor that its front side layer was filled with deionized water instead of phycocyanin. The photobioreactors were placed under 490 μmol photons m⁻²s⁻¹ at 27 ± 1°C for 14 days. Results showed that, phycocyanin solution increased biomass productivity rate and maximum specific growth rate 28% and 40%, respectively. Also, chlorophyll a content has increased up to 34% at the end of the cultivation. But lipid content is decreased due to the spectral conversion by phycocyanin. Generally, spectral conversion using phycocyanin caused increasing in biomass productivity rate and chlorophyll content of microalgae Chlorella sp..