The influences of different light qualities (green 510-550 nm, blue 455-475 nm, red 580-630 nm, white 400-760 nm) from light-emiting diode (LED) illuminations on the growth and physiological characteristics of wild free-living conchocelis of Pyropia haitanensis were studied. Results showed that blue light (BL) significantly promoted the growth rate of conchocelis in the cultures. The weight increments of conchocelis under BL were 1.10, 1.82, 2.17 times higher than those of other conchocelis cultured under white light (WL), green light (GL) and red light (RL), respectively. BL stimulated the synthesis of chlorophyll a and carotenoids. Compared to WL, GL and RL, the contents of chlorophyll a in BL were increased by 13.77%, 47.69%, 63.42%, respectively, and the contents of carotenoids in BL were increased by 8.87%, 87.07%, 97.73%, respectively. BL and WL were conducive to synthesize phycoerythrin rather than GL and RL. However, there were no significant differences of phycocyanin contents between the conchocelis in the cultures under different LED light qualities. Moreover, BL resulted in the highest activity of carbonic anhydrase, which enhanced by 11.36% than those of WL. Compared to WL, both BL and GL significantly stimulated the activity of ribulose bisphosphate carboxylase, which enhanced 28.17% and 61.21%, respectively. In the late growth stage, the conchocelis cultured under RL and GL were discolored and short of satellite chromatophore, even parts of them overflowed their cell inclusions and were hollowed. Whereas, conchocelis under BL and WL were normal, healthy and bright red. Therefore, we could add suitable component of blue-light, and decrease red-light and green-light in the asexual propagation of free-living conchocelis in P. haitanensis.