Chroococcus westii is a species of cyanobacteria in the family Chroococcaceae, likely named in honor of a naturalist or phycologist named West, following the common nineteenth and early twentieth century tradition of naming newly described microorganisms after prominent researchers in the field. The species belongs to a genus of simple, spherical cyanobacteria that occur in pairs or small groups within gelatinous sheaths in freshwater and aquatic environments. Chroococcus westii has been documented from freshwater habitats, contributing to the cyanobacterial diversity of lakes, pools, and associated periphyton communities. Cyanobacteria of the Chroococcaceae are among the foundational components of freshwater microbial ecosystems, contributing to primary production, biofilm formation, and in some lineages, biological nitrogen fixation. The taxonomy of the genus Chroococcus has undergone revision through the application of modern molecular phylogenetic methods, which have revealed that morphologically similar coccoid cyanobacteria can be phylogenetically distant, suggesting the need for further taxonomic work. Chroococcus westii is a relatively obscure species documented primarily in classical phycological literature. It has not received formal IUCN assessment.