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<i>Haematococcus pluvialis</i> undergoes a three-phase process during the process of germination: first, repeated mitotic events; next, cytokinesis to form the zoospore; and finally, a fast release of motile cells. Physiological properties were measured using chlorophyll <i>a</i> fluorescence (OJIP) transient. The most obvious increase in K-value and L-value appeared at 17 h, suggesting that oxygen-evolving complex damage and lower energetic connectivity of the photosystem II units of the mother non-motile cell occurred. Compared to phase I, the values of the maximum quantum yield of PSII photochemistry (F_V/F_M) and PI_ABS increased significantly in phases II and III, suggesting that photosynthetic photochemical activity was greatly up-regulated during cytokinesis to form zoospores and the fast release of motile cells. Moreover, the significant increase in the K-band at 17 h and 22 h indicates that the PSII donor side was the limiting factor during the initial period of germination. All these results suggest that the cellular photosynthetic activity continues to strengthen during cytokinesis to form the zoospore and the fast release of motile cells, and it was postulated to meet the demands for sporangium swelling and new organelle formation.