Pyrimidine is a six member heterocyclic ring having two nitrogen (N) atom 1, 3 position. Chemistry of pyrimidine is a blossoming field. Various methods for synthesis of pyrimidine and also their diverse reactions allows enormous in the field of medicinal chemistry. Pyrimidine not only has a wide range of pharmacological and biological activities but there are several established protocols to synthesize this ring. Pyrimidine ring has been found to possess anti-malarial, anti-bacterial, antifungal, anticancer, anticonvulsant, anti-inflammatory, and analgesic activity. This book reports about the pyrimidine derivatives having a variety of biological activities.