The breakdown voltage of 4H-SiC junction barrier schottky diode with floating junction is larger than that of traditional junction barrier Schottky diode under the condition of the same fixed on-resistance. It is a crucial technology that the alignment of lithography between p+ region of floating junction and main junction. The simulation results obtained using two-dimensional simulator ISE show that the breakdown voltage obviously drops with the deviation of lithography increasing. Although the breakdown characteristics of the dislocation and the alignment structure are similar, the series resistance of the dislocation structure is larger than the latter when the forward voltage is larger than 2 V.