N-Octanoyl chitosan (NOC) and N-Palmitoyl chitosan (NPC) were synthesized to modified chitosan hydrophobically and characterized by FTIR, NMR, XRD, modified chitosan were having about 14 % degree of substitution and improvement in solubility in solvent. Full 32 factorial designs were used to optimize ionotropic method to prepared ropinirole loaded nanoparticle of chitosan and modified chitosan. Concentration of N-acyl chitosan, TPP and stirring speed was independent parameter while mean particle size and entrapment were dependent variable. 3D surface plot and counter plot of optimized batch was draw. Average particle size, drug loading and entrapment efficiency of ropinirole loaded nanoparticle was 150.7±3.3 nm, 24.80±1.1% and 54.96±3.8% respectively which were correlated with increases bulkiness of the acyl substitution in the modified chitosan while zeta potential was found inversely correlated. TEM and SEM imaging relieved spherical structure of nanoparticle. In vitro release of ropinirole in 1.2 pH HCl buffer and pH 7.4 phosphate buffer showed biphasic release pattern best fitted with Korsemeyers-Peppas kinetics with fickian transport mechanism. Acylated chitosan showed enhancement of sustained release with increasing length of acyl group. Result of the present study showed that hydrophobically modified acylated chitosan can be useful for achieving sustained release controlled by acylation modification.