Asymmetric composite membranes of cellulose acetate (CA)/hydroxyapatite (HA) are prepared using phase inversion method for the separation of water, urea, glucose, and protein. Various concentrations of HA up to 15 wt% are dispersed uniformly in the CA matrix. The pore size of the CA matrix is tunable by varying the concentration of HA. The flux of water, urea and glucose is 7 times higher while for BSA 12 times higher in CA/HA composite membranes than pure CA. Similarly, water absorption capacity of CA/HA composite membranes are increased owing to the incorporation of hydrophilic HA in CA matrix. Moreover, the retention rates are also reasonable in CA/HA composite membranes depending on the difference in porosity of the membranes. The permeation of urea is much higher in the CA/HA composite membranes as compared to pure CA, which is more suitable for hemodialysis. Thereby, such CA/HA composite membrane offers the potential to be used in hemodialysis applications.