The DSC curve of melting and crystallization of high pressure polyethylene was simulated with divided difference interpolation by means of the algebraic polynomial Pn (X) = f(x0) + f(x0

x1)(x-x0) + f(x0

x1

x2) (x-x0) (x-x1+…+ f(x0

X1

…xn) X (x-x0)(x-X1)…(x-xn-1). For the convenience of calculation

the above polynomial was changed into following formula Pn (x) = [{[f(x0…xn) (x-xn-1) +f(x0…x0-1)](x - xn-2) +…+f(x0

x1

x2)} × (x-x1) + f(x0

x1)] (x-X0)+f(x0)(Ⅰ)A programm was written using both (Ⅰ) and Simpson formula. The coordinate of the sum of points and the peak areae of DSC curve had been calculated by microcom-puter. Comparison with “to count mm-check”and “cut and weigh”methods gives good agreement. It shows that the above method is convenient and applicadle.