A boost control apparatus that is configured to control a converter comprising a first switching element and a second switching element, each of which being connected to an inductor in series, and to realize one-side element control, during which only either one of the first switching element and the second switching element is driven, said boost control apparatus comprising: a current value change amount detecting device configured to detect a change amount of output current that flows through the inductor in a first predetermined period during the one-side element control; a determining device configured to determine that the output current is near zero; and a controlling device configured (i) to perform first duty control if it is not determined that the output current is near zero, and (ii) to perform second duty control if it is determined that the output current is near zero; wherein the first duty control and the second duty control are controls for changing a duty ratio of the first switching element or the second switching element and the first duty control is configured to use a first control parameter and the second duty control is configured to use a second control parameter which is different from the first control parameter; the boost control apparatus being characterized in that: said current value change amount detecting device is configured to detect the output current a predetermined number of times at regular intervals, three times or more, in a second predetermined period, which is immediately before the first switching element or the second switching element is turned on and to detect the change amount based on said detection of the output current a predetermined number of times at regular intervals; said determining device is configured to determine that the output current is near zero, if a predetermined number of change amounts or more out of a plurality of change amounts are less than a predetermined threshold value; the first control parameter and the second control parameter include set feed-forward terms that are different from each other; and a duty ratio corresponding to the output current in the second duty control is configured to be set to be greater than a duty ratio in the first duty control due to the difference between the feed-forward terms. a current value change amount detecting device configured to detect a change amount of output current that flows through the inductor in a first predetermined period during the one-side element control; a determining device configured to determine that the output current is near zero; and a controlling device configured (i) to perform first duty control if it is not determined that the output current is near zero, and (ii) to perform second duty control if it is determined that the output current is near zero; wherein the first duty control and the second duty control are controls for changing a duty ratio of the first switching element or the second switching element and the first duty control is configured to use a first control parameter and the second duty control is configured to use a second control parameter which is different from the first control parameter; the boost control apparatus being characterized in that: said current value change amount detecting device is configured to detect the output current a predetermined number of times at regular intervals, three times or more, in a second predetermined period, which is immediately before the first switching element or the second switching element is turned on and to detect the change amount based on said detection of the output current a predetermined number of times at regular intervals; said determining device is configured to determine that the output current is near zero, if a predetermined number of change amounts or more out of a plurality of change amounts are less than a predetermined threshold value; said current value change amount detecting device is configured to detect the output current a predetermined number of times at regular intervals, three times or more, in a second predetermined period, which is immediately before the first switching element or the second switching element is turned on and to detect the change amount based on said detection of the output current a predetermined number of times at regular intervals; said determining device is configured to determine that the output current is near zero, if a predetermined number of change amounts or more out of a plurality of change amounts are less than a predetermined threshold value; the first control parameter and the second control parameter include set feed-forward terms that are different from each other; and a duty ratio corresponding to the output current in the second duty control is configured to be set to be greater than a duty ratio in the first duty control due to the difference between the feed-forward terms.