Phosphoribosyl pyrophosphate synthetase (PRS) 1, encoded by PRPS1 gene, is the first limiting enzyme participating in the synthetic process of nucleic acids. Consequently, it has a great effect on cell functions, especially the synthesis and metabolism of purine and pyrimidine. Some changes in PRS1 crystal structure might exert inconceivable effects on enzyme activity and lead to disorder of purine/pyrimidine metabolism, even cellular energy metabolism failure. Inherited mutation may induce disfunction of some energy-intensive tissue, the common clinical manifestations are some clinical syndrome. In addition, PRPS1 mutations found in cancer are proved to be an important cause of tumor resistance, followed by patient relapse. In a word, PRS1 plays a key role in energy metabolism, signal transduction and nucleic acid synthesis, which is of great significance in maintaining physiological activities. This article mainly focuses on the physiological functions and crystal structure of PRS1, the regulation of cell metabolism by PRPS1 gene and its mutations, as well as clinical syndromes related to PRPS1 gene mutation.