Breast and ovarian cancers are common malignant diseases of gynecologic cancer. Many researches revealed the relation between these cancers and BRCA1 and BRCA2 mutations. Two genes that are susceptible genes produce proteins which join basic cellular processes: remain the intactness of genome and regulation duplicative processes. There are many kinds of mutations of BRCA1 gene which are reported in Genbank. The mutation screening is difficult due to the big size of this gene, without hotspot mutation and the ethnical variability. Object: Detection mutations of exon 11 of BRCA1 gene in breast - ovarian cancer patient. Method: Analyse exon 11 of BRCA1 gene of 6 breast ovarian cancer patients by PCR- direct sequencing. Results: Detect two patients with mutation, one patient with SNP (single nucleotide polymorphism) c.2612CT and c.3042deIA, one patient with SNP c.2612CT. c.3042de1A is the new mutation, which is not reported in Genbank.