Both thermoresponsive flat membranes and core-shell microcapsule membranes, with (N-isopropylacrylamide) (PNIPAM) a porous membrane substrate and grafted poly N-isopropylacrylamide PNIPAM gates, were successfully prepared using a plasma-graft pore-filling polymerization method. PNIPAM was prepared to be grafted homogeneously onto the porous membrane sub-strates, in the direction of both the membrane thickness and surface. Regardless of the solute molecular size, temperature had an opposite effection diffusion coefficients of the solute across the PNIPAM-grafted membranes with low graft yields as opposed to those with high graft yields. The PE-g-PNIPAM membranes change from positive thermo-response to negative thermoresponse types with increasing pore-filling ratios at around 30%. Phenomenological models were developed for predicting the diffusion coefficient of the solute across PNIPAM-grafted membranes at temperatures, both above and be-low the lower critical solution temperature LCST. Predicted diffusional coefficients of solutes across both the PNIPAM-grafted flat and PNIPAM-grafted microcapsule membranes fit the experimental values. To obtain an ideal result for the diffusional thermoresponsive controlled release through PNIPAM-grafted membranes, the substrates strong enough to prevent any conformation changes are more suitable for preparing thermoresponsive membranes than weak ones.