A method for positioning an operating unit of an electrically-operated injection molding machine at a predetermined operating position in an optimum manner, by using widths of positive-side and negative-side regions of an allowable positioning zone which are set independently of one another in accordance with the operating direction of the operating unit and the function to be achieved by the operating unit. Positioning of a screw at an injection-end position is completed when the actual screw position (PA) is equal to or less than the sum of a target injection-end position (PS) and the positive-side region width (W1), which is set to "0", and is equal to or larger than the value obtained by substracting the negative-side region width (W2) from the target position (PS), so that the screw is positioned at the target injection-end position or a screw-moving position which slightly exceeds the target position by a permissible distance, to thereby actually control an amount of shot.