A method is established that uses only two characteristic points df a single non-isothermal DSC curve, (d/dT)(d alpha/dt) = 0 and (d(2)/dT(2))(d alpha/dt) = 0, from the classic isothermal kinetic equation d alpha/dt = AS(alpha)e(-E/RT). Using this method, it is very easy to estimate the non-isothermal kinetic parameters of activation energy E and pre-exponential factor A and to select the most probable mechanism function from those commonly used; this may increase our understanding of the experimental phenomena. Two indexes of peak shape are defined for judging whether the peak is treatable or not. A typical calculation is given. The computed results for E and A coincide very well with those derived by commonly used methods; the selected mechanism function is also reasonable.