Disclosed is a control method of a washing machine. The method includes accelerating an angular speed of a wash tub by rotating the wash tub in which water is stored in a washing or rinsing operation, and detecting current angular-speed values with a time gap within a preset preliminary-acceleration range, thereby calculating a preliminary angular-speed variation-value by adding absolute values of differences between the current angular-speed values detected before and after each time gap, comparing the preliminary angular-speed variation-value with a preset preliminary reference variation-value to perform fabric dispersion when the preliminary angular-speed variation-value exceeds the preliminary reference variation-value, and discharging the water and rotating the wash tub so that the angular speed of the wash tub is accelerated in a dehydration operation. The preliminary reference variation-value is preset to the preliminary angular-speed variation-value, calculated when an eccentric rotation degree of the wash tub is a preset maximum tolerance value.