A flush toilet device has a toilet body having a bowl section, rim water discharge opening, a jet water discharge opening, and a discharge water trap conduit. A pressurizing pump is provided for pressurizing flush water contained in a cistern to supply it to the jet water discharge opening. A pump controller regulates the operation and rotation speed of the pressurizing pump to regulate the flow speed and flow rate of flush water discharged from the jet water discharge opening so that flush water at a first flow rate for generating a siphon effect is discharged and then at a second flow rate is discharged at the end of the siphon effect generated by the first flow rate. The second flow rate having a flow speed that can carry away human wastes and causes the siphon effect to continue by closing the cross section of any portion of the discharge water trap conduit.