In this study, poly(L-lactide) (PLA) nanoparticles containing amphotericin B (AmB) were developed, and the in vitro cytotoxicity to human erythrocytes and efficacy on strains of Candida spp. were evaluated. The nanoparticles were prepared using an emulsion/solvent evaporation method and were characterized with respect to size, size distribution, AmB encapsulation efficiency, AmB state of aggregation, and AmB in vitro release profile. The mean particle size was 225 nm, and the AmB encapsulation efficiency was over 69%. The AmB in vitro release profile revealed a burst effect within the first 24 h, which released approximately 10% of AmB, followed by a sustained release of approximately 30% of AmB over 30 days. The AmB nanoparticles presented a very low index of hemolysis compared to free AmB, which lysed more than 80% of erythrocytes in the first 2 h of incubation. The AmB-loaded PLA nanoparticles were as effective as free AmB against strains of Candida spp., considering their sustained release profile. Thus, PLA nanoparticles can deliver AmB with reduced toxicity while maintaining its antifungal activity.