Provided is a small-sized electrophotographic apparatus having a double face printing function, which can print at a high speed even during double face printing. There are provided a recording medium conveying path 5 composed of a vertical conveying path 5a for upward conveying a sheet fed from a sheet cassette 2, outside of a developing means 60, a curved conveying path 5b and horizontal conveying path 5c for conveying the recording medium to a transfer means 50, a fusing means 51 located in the horizontal conveying path 5c, downstream of the transfer means 50, for fusing a toner image on the recording medium 2, a sheet discharge tray 53, a bypass conveying path for guiding a sheet to be subjected to double face printing, having one surface for which printing has been completed, a first branch means 58 for guiding the sheet to be subjected to double face printing from a conveying path for the sheet discharge tray 53 into the bypass conveying path 56, a reversing conveying path 54 for reversing the sheet conveyed in the bypass conveying path 54 during double face printing, a second branch means 59 for guiding the sheet which has been reversed in the reversing conveying path 54, into the horizontal conveying path 5c, and a return conveying path 57 for returning the sheet which has passed through the second branch means 59, into the return conveying path 57 for conveying the sheet to the horizontal conveying path.