A steel magnet body assembly comprises a first magnetizer (1) and a second magnetizer (2) that are magnetically conductive, and comprises multiple steel magnets (3). A magnetically insulative fixing member (4) used for fixing the steel magnets (3) are disposed between the first magnetizer (1) and the second magnetizer (2). The first magnetizer (1), the fixing member (4) and the second magnetizer (2) are sequentially stacked. The multiple steel magnets (3) are fixed in the fixing member (4) in an evenly spaced manner. Each steel magnet (3) is a column having an N magnetic pole and an S magnetic pole, and the N magnetic pole and the S magnetic pole of the steel magnet (3) are relatively disposed on two sides of a plane where the central axis of the column of the eel magnet (3) is located. The steel magnet body assembly enables a steel magnet to be conveniently magnetized, and enables the tensity of a magnetic field to be uniform after the magnetization. The steel magnet body assembly also has a high residual magnet ism, a high coercivity and a high magnetic energy product, and the stability and sensitivity of the steel magnet body assembly are improved.