Theoretical analysis reported in this paper is on the varities of the growth rate of Chlorella ellipsoidea due to the amount of available phosphorus for the purpose of the continual mass culture. Available phosphorus in the culture media of the Chlorella was also estimated at a limiting factor as this experiment. The equation between the concentration of Chlorella n and growth period t is $frac{dn}{dt}=Kn$, and the functional relation between the Specific growth rate K and steady state period T is the following: $K=frac{2.303}{T}$<TEX$>logfrac{n}{no}$</TEX> ($n_o$=initial concentration).