Chloroquine phosphate loaded PLGA nanoparticles were prepared using the modified nanoprecipitation method. PLGA is a synthetic copolymer that can be easily functionalized to achieve desired outcomes. PLGA nanoparticles are biodegradable, biocompatible, non-toxic and easily prepared.The primary focus of the study was concerned with the preparation of Chloroquine phosphate-loaded PLGA nanoparticles in order to improve drug tolerance, reduce the frequency of doses and less toxic. Formulation of nanoparticles were characterized for encapsulation efficiency using UV-vis. spectroscopy; particle size distribution, polydispersity index, and zeta potential using photon correlation spectroscopy; and in vitro drug release profile using UV-vis. spectroscopy. The sizes of nanoparticles formulation were 152.3 nm, polydispersity index is 0.272, encapsulation efficiency was 75 % and drug loading efficiency was 60 % respectively. Ready nanoparticles were spherical shape, smooth surface and free-flowing nature.In vitro drug release studies showed that prepared nanoparticles-maintained drug release over 24 hours. Infra-red (IR) spectra showed the stability of Chloroquine phosphate loaded PLGA nanoparticles and the absence of drug-polymer interactions.