An image forming apparatus, comprising: an image forming portion (1117, 1119, 1107, 1120, 1121) that forms an image on a recording material; a fixing portion (1109, 1203, 1220) that fixes the image on the recording material by heating, a temperature detection element for detecting the temperature of the fixing portion; a control portion for controlling a power ratio of electric power supplied to the fixing portion in accordance with a temperature detected by the temperature detection element so that the fixing portion is maintained at a control target temperature (Tf); characterized by a first current detection circuit that detects an input current from a commercial power supply to the apparatus; a second current detection circuit that detects a current to the fixing portion; wherein in a case where a current detected by the first current detection circuit exceeds a predetermined value, a maximum current suppliable to the fixing portion is restricted by electrifying the fixing portion with the smallest of: a power ratio (Dp) set according to the detection temperature of the temperature detection element; a power ratio (Di) set according to an output of the first current detection circuit and a power ratio (Df) set according to an output of the second current detection circuit, and further wherein if, whilst the maximum current suppliable to the fixing portion is restricted in response to the first current detection circuit detecting that the input current exceeds the predetermined value, the temperature detection element detects that the temperature of the fixing portion falls below a predetermined temperature (Tb), lower than the control target temperature, a conveyance interval of the recording material conveyed to the fixing portion is extended. an image forming portion (1117, 1119, 1107, 1120, 1121) that forms an image on a recording material; a fixing portion (1109, 1203, 1220) that fixes the image on the recording material by heating, a temperature detection element for detecting the temperature of the fixing portion; a control portion for controlling a power ratio of electric power supplied to the fixing portion in accordance with a temperature detected by the temperature detection element so that the fixing portion is maintained at a control target temperature (Tf); characterized by a first current detection circuit that detects an input current from a commercial power supply to the apparatus; a second current detection circuit that detects a current to the fixing portion; wherein in a case where a current detected by the first current detection circuit exceeds a predetermined value, a maximum current suppliable to the fixing portion is restricted by electrifying the fixing portion with the smallest of: a power ratio (Dp) set according to the detection temperature of the temperature detection element; a power ratio (Di) set according to an output of the first current detection circuit and a power ratio (Df) set according to an output of the second current detection circuit, and further wherein if, whilst the maximum current suppliable to the fixing portion is restricted in response to the first current detection circuit detecting that the input current exceeds the predetermined value, the temperature detection element detects that the temperature of the fixing portion falls below a predetermined temperature (Tb), lower than the control target temperature, a conveyance interval of the recording material conveyed to the fixing portion is extended.