The chaos of heart rate variance (HRV) is identified by surrogate data method in this paper. Firstly, the main principle of chaotic identification is introduced, in which the median absolute error (MAE) of one-step prediction for HRV is set as the statistic. The algorithm is checked with a known chaotic system response and a colored noise signal. Then, some typical healthy and unhealthy HRVs are analyzed with the method of surrogate data, and some characteristic parameters from this method are compared.