Inositols are used as growth promoting agents over plants. But microalgae are different from higher plant especially photosynthetic efficiency and productivity. According to the results of this study, myo-inositol addition to the culture medium of Nannochloropsis oculata provides higher cell densities. 100 mg L-1 myo-inositol added experimental group was reached to 1.42 fold cell mL-1, while the 500 mg L-1 myo-inositol added group was reached to 1.28 fold cell mL-1 than the control group. Mean chlorophyll a per cell amounts were calculated for experimental groups and control groups as 0.052 pg cell-1 and 0.053 pg cell-1, respectively. Mean total carotene per cell amounts were calculated for all groups as 0.016 pg cell-1. These results show that no difference was occurred between all groups by chlorophyll a and total carotene amounts per cell. This study shows that myo-inositol use in microalgae production may provide higher yields.