An image forming apparatus has sufficient fixing stability and load capacity
and
being free of sheet jamming and poor image formation. An image forming apparatus
includes a transfer voltage applying section for applying a voltage to a transfer
section; a transfer current detector for detecting the transfer current flowing
through the transfer section; a fixing section for fixing the toner image to fixing
position at a predetermined temperature; and a size detector for detecting the
size of the recording material. The transfer voltage applying section applies a
predetermined transfer voltage, while the recording material passes through the
transfer section, so that the transfer current is kept a constant current. When
the predetermined transfer voltage is lower than a threshold voltage and the size
of the recording material is larger than the predetermined size, the fixing section
fixes the toner image at a temperature which is lower than the predetermined temperature.