Purpose: To analyse of false negative result of fine needle sapiration of palpable breast lesion. To understand the cause of false analysability. Object and methods: 168 cases of false - negative diagnoses from fine needle aspiration of breast lesion in Vietnam-Cuba Dong Hoi friendship hospital from 2002 to 2011. Results: The following factors are found to be associated with false-negative resuls of lesion: The influence of unsatisfactory samples: 57.7 percent , including leaving out the details of cancer cell in samples: 3.1 percent. The evalutions of samples are errors: 42.3 percent, (the breast proliferative lielons: 83 percent, the breast diffuse lesions: 73.2 percent, small tumor size below 2cm: 22.6 percent, lobulor carcinoma: 57.8 percent). Conclusions: Fine needle aspiration can play a significant role in the dianosis of breast disease, if its limitation are the clearly understood by clinican and the potential causes of false-negative diagnosis are remembered by the pathologist. The principle to be abided by fine needle aspiration is find out the position of the injuries and have enough suitabe cell compositions for evalution. Repeat fine needle aspiration is always warranted.