1. A magnetic resonance imaging apparatus comprising: a plurality of receiving coils for receiving a magnetic resonance signal generated from an object to be examined; sensitivity image data acquiring, means for acquiring sensitivity image data by executing a first pulse sequence using the plural receiving coils from a plurality of slice positions separated from each other at intervals on the object; means for acquiring examination image data of each of the plural receiving coils from the plural slice positions sequentially adjoining on the object by executing a second pulse sequence using the plural receiving coils while a phase encoding matrix in a k space is thinned out; and artifact removing means for generating sensitivity distribution data of the plural receiving coils on the slice positions of the examination image data on the basis of the plural sensitivity image data and removing an aliasing artifact in the examination image using thus generated sensitivity distribution data of the receiving coils.