There is statistical fluctuation of measurement value when the ore pulp density is measured on-line with radiation, In order to decrease statistical error, longer measuring time should be adopted by radiation ore pulp density gauge to perform meas- urement. However, the gauge cannot respond quickly and dynamic measurement error will be higher due to longer measuring time when input signal changes rapidly. In order to solve this problem and to rise the measuring accuracy, fuzzy logic was employed to control the signal processing of the gauge. A filtering algorithm was developed and the filter c...