Abstract: In order to recognize time－sequence curves,along with the x－axis direction and by means of averagely dividing 0°～180° into small intervals,standard codes are adopted to express the general tendence of the curves in general.On the basis of standard codes,corresponding revisal codes are also adopted to express the deviation from standard codes.In fact,both codes describe the shapes of curves exactly.A similarity function is defined to compute the similarity between a curve and another one,which in most cases are not of the same length.The method described above is proved effective in the recognition of sediment microfacies by well－logging curves from the Luliang Area of Xinjiang Kelamayi Oil Field．