Rubella is Togaviridae family, ARN virus. Recent years, the outbreaks of Rubella fever in Vietnam was complicated. Cycle of epidemic is 5-year. Rapid and accurate diagnosis is good for effective control of outbreaks, especially in prenatal diagnosis. In this study, nested RT-PCR technique was established for detecting ARN of rubella virus, diagnosis of viral infection. This technique can detect rubella rapidly and exactly.