In order to study the effects of exogenous 5aminoacetyl propionic acid (ALA) on the growth and chlorophyll fluorescence induction kinetics of Scenedesmus obliquus, we spiked ALA to cultured S. obliquus, using two methods onetime spike (ALA) or everythreeday spike (CALA) and tested its growth response at 5, 15, and 25 ℃, respectively. The chlorophyll fluorescence parameters were measured in the logarithmic phase. The results illustrated: (1) A consistent pattern at 5 and 15 ℃ for ALA treatment, which had the greatest maximum growth rate (μ_max) and we tested a 122.7% and 126.8% increase of μ_max related to the control. (2) The μ_max of CALA was higher than that of control, suggesting that adding ALA can promote the growth of S. obliquus, particularly at 5 ℃ where a more evident significance observed. Furthermore, the decline of the maximum quantum yield of primary photochemistry (F_v/F_m) and the performance index on absorption basis (PI_ABS) were significantly lower with ALA treatment than that of control. Besides, the parameter of F_ok, F_kj, F_ji, and F_ip were significantly higher than that of CK. (3) By analyzing the JIPtest parameter, we observed a reduced light energy absorbed by the active reaction center of S. obliquus with ALA treatment in addition to a declined heat dissipation, indicating that more energy can pass through the electron transport chain and participate in photochemical reactions. Visible, these evidences support the view that exogenous ALA can promote the growth of S. obliquus to some extent, and the promoting effect is more obvious in 5 ℃ low temperature; ALA treatment can boost the photosynthetic efficiency, improving the Q_A, Q_B, and PQ significantly (P<0.05); the ALA significantly protect PSⅡ with the environmental temperature decreasing within a certain temperature range