Understanding the cellular and molecular biology of any infectious agent is the mainstay of its successful prevention and control. Therefore, in this review, various aspects of the cellular and molecular biology of the Plasmodium parasite were critically reviewed. Plasmodium parasite is characterized by the presence of three different invasive forms (Sporozoites, Merozoites, and Ookine/Oocyte), which are morphologically and genetically distinct. The size of the Plasmodium genome, which comprises nuclear, plastid, and mitochondrial genomes ranges in size from 20 to 35 megabase (Mb) with 23 million bases, which translate into 7132 genes in Plasmodium ovale and 5507 in Plasmodium falciparum. Plasmodium species are found to be the most AT-rich genome (80%), and their GC% contents are merely less than 20%. Gametocytogenesis indicates the commencement of the sexual development, which is regulated by signal transduction and expression of genes such as Pfs16, Pf14.744, Pf14.748, Pfpeg3/mdv1, and Pfpeg4. In these stages, only 20% of all Plasmodial genes are expressed.