A apparatus includes an acquisition unit to acquire magnetic resonance data in every data group, a unit to control the acquisition unit to collect the data for one or a plurality of data groups during a collection period which is set based on a starting time phase of a cardiac cycle of the subject, a unit to determine the data among the data acquired by the acquisition unit as ineffective data if at least a part of it is related to a data group acquired during an ineffective period, and as effective data if all of it is related to a data group acquired during a period other than the ineffective period, the ineffective period being set based on an ending time point of the cardiac cycle in which the data is acquired, and a unit to reconstruct an image regarding the subject by using the effective data.
