By using three strains (two improved strains (SF-1 and SF-2) and the wild type (WT)) of free living conchocelis of Prophyra haitanensis, the optimal transplanting quantity and the influence of the initial density of conchocelis colony, photon flux density and temperature for vegetative growth of conchocelis and the conchospore number of conchocelis were studied. The results indicated that the initial density of conchocelis colony significantly increased with the increase of transplanting quantity in range of 50-500 mg/m². However, when the tansplanting quantity was higher than 100 mg/m², the conchospore number decreased. Increase of photon flux density within the range of 10-50 μmol photons/（m²·s）accelerated the vegetative growth of conchocelis, but decreased the conchospore number. Increasing temperature within the range of 15-25 ℃ accelerated the vegetative growth of conchocelis. However, the conchospore number increased with the increase of temperature from 15 to 20 ℃, and decreased with the increase of temperature from 20 to 25 ℃. The vegetative growth and conchospore number of SF-1, SF-2 and WT strains showed no significant differences. The above results indicated that higher transplanting quantity, photon flux density and temperature in culture of conchocelis will reduce the conchospore number of conchocelis when seeding with free living conchocelis in P. haitanensis.