Square GdBaCuO bulks with 45.2 ×45.2 mm2 in the a
b-plane and 15 mm in thickness along the c-axis with different arrangements of growth sector boundaries (GSBs) were magnetized by a field-cooled magnetization (FCM), a zero-field cooled magnetization (ZFC), and a pulsed-field magnetization (PFM) and the trapped field profiles were measured. For the lower applied field in ZFC, the magnetic flux was trapped in the growth sector regions (GSRs), independent of the arrangement of GSBs. For the lower applied field in PFM, the magnetic flux was mainly trapped in the GSRs and an additional flux was also trapped at the sides in both bulks because of the complicated flux intrusion by the local heat generation. These bulks can trap a magnetic field as high as 7.5 T at 50 K by FCM without destruction. The magnetic flux intrusion and trapping for the square bulks were discussed.