In the experiment, we investigatd the effects of temperature alteration on light energy utilization and growth of Cholorella pyrenoidosa Chick. growing under different light intensity conditions, and aimed to ascertain whether the influence of light intensity on light energy utilization and growth of phytoplankton is affected by temperature. Three light levels (50，150，300μmol•m^-2•s-1) and two temperature levels (15℃，25℃) were included in the experiment. It was found that the non-photochemical quenching (NPQ) of chlorophyll fluorescence of C. pyrenoidosa cultivated under different light intensity conditions was influenced by temperature. At light intensities of 150 and 300 μmol•m^-2•s^-1, temperature elevation led to an increase of NPQ, and the higher the light level, the larger increase in NPQ of C. pyrenoidosa. At light intensity of 50μmol•m^-2•s^-1, however, temperature elevation did not affect NPQ of C. pyrenoidosa. As regards photosynthetic electron tranport rate of C. pyrenoidosa, it was revealed that the increase of electron tranport rate with light intensity at 25℃ was lower than that at temperature of 15℃. Moreover, the suppression effect of temperature elevation on the electron transport rate of C. pyrenoidosa increased with light intensity significantly. As far as the growth of C. pyrenoidosa is concerned, it was shown in the experiment that at temperature of 15℃, the chlorophyll a concentration of C. pyrenoidosa culture solution rised gradually with light intensity, and the highest chlorophyll a concentration of the solution was reached at 300μmol•m^-2•s^-1. However, when the temperature was 25℃, chlorophyll a concentration of C. pyrenoidosa solution did not increase with light intensity, the chlorophyll a concentration of C. pyrenoidosa solution cultivated at 300μmol m^-2•s^-1 was lower than that of C. pyrenoidosa at 150μmol•m^-2•s^-1. Our research clearly demonstrated that temperature elevation enhanced the dissipation of absorbed light energy as heat of C. pyrenoidosa exposed to high light intensity conditions, and therefore reduced the positive effects of light intensity augmentation on the growth of C. pyrenoidosa. The optimal light levels for growth of C. pyrenoidosa was lowered at higher temperature due to the suppression effect of temperature elevation on light energy utilization and growth.