Abstract:  Objective To report the clinical manifestation and gene mutation of congenital insensitivity to pain with anhidrosis (CIPA) in two patients from one family. Methods The data of clinical manifestation, laboratory examination, and family history of two patients were collected. The peripheral blood of patients and their parents were collected. Neurotrophic tyrosine kinase receptor type 1 (NTRK1) gene was detected directly by Sanger method, the pathogenicity of the mutation in the gene was analyzed by bioinformatics. Results Both of patients were female and mainly suffered with reduplicated non-infectious fever, anhidrosis, insensitive to pain, and mental retardation. The proband had fracture many times after minor injury. The ninth exon of NTRK 1 genes in the proband and her younger sister were found to have heterozygous mutations, c.851-33T>A, as previously reported. Meanwhile, there was also found a new mutation, c.1711G>A (p.G571S), in thirteenth exon of NTRK 1 genes in these two patients. It was predicted to be a harmful mutation by bioinformatics and the mutation site is conservative. Their father and mother were found carrying the c.851-33T>A and c.1711G>A mutations respectively. Conclusion Both patients had typical clinical manifestations. And the newly discovered p.G571S mutation expands the mutation spectrum of NTRK 1 gene.