Nonlinear science research is a hot point in the world. It has deepened our cognition of determinism and randomicity,simplicity and com-plexity, noise and order and it wilI profoundly influence the progress of the study of naturaI science, including life science. Life is the most complex nonlinear systern and heart is the core of lifecycle systern. In the Iate more than 20 years. nonlinear research on heart elect ric activities has made much headway. The commonly used parameters are based on chaos and fractaI theow, such as correlation dimension, Lyapunov ex-ponent, Kolmogorov entropy and multifractal singu-larity spectrum. This paper summarizes the commonly used methods in the nonlinear study of heart electric signal Then, considering the shortages of the above tradi-tionaI nonlinear parameters. we mainly introduce the results on short-term heart rate variability (HRV) signaI(500 R-R intervals)and HFECG signaI(1-2s). Finally,we point out it is worthwhile to put em phasis on the study of the sensitive nonlinearity parameters of short-term heart electric signaI and their dynamic character and clinicaI efectivity.