Image forming apparatus and method for transporting sheet thereof

An image forming apparatus comprising:

• a first sensor which is provided on a transportation path of a sheet and detects a first passage time of the sheet;
• a second sensor which is provided at a position different from the position of the first sensor in a transportation direction of the sheet and a direction perpendicular to the transportation direction and detects a second passage time of the sheet;
• a skew determination unit which determines a skew amount of the sheet based on a difference between the first passage time detected by the first sensor and the second passage time detected by the second sensor;
• a correction control unit which performs control for correcting a skew of the sheet on the basis of the skew amount determined by the skew determination unit;
• and
• a display unit which displays a message indicating that the skew amount is larger than a predetermined reference value, if the skew amount determined by the skew determination unit is larger than the predetermined reference value.