A detecting apparatus, comprising: a first sensor including a first applying electrode (401a - 401e) and a first detecting electrode (401a - 401e) that are opposed to each other, the first sensor being coupled to an electric current detection circuit for detecting electric current in the first detecting electrode (401a - 401e) based on a change in electrostatic capacitance when a piece of paper passes between the first applying electrode (401a - 401e) and the first detecting electrode (401a - 401e); a second sensor including a second applying electrode (403a - 403e) and a second detecting electrode (403a - 403e) that are opposed to each other, the second sensor being coupled to an electric current detection circuit for detecting electric current in the second detecting electrode based on a change in electrostatic capacitance when a piece of paper passes between the second applying electrode (403a - 403e) and the second detecting electrode (403a - 403e); a conveyance path (a) configured to convey the piece of paper between the first applying electrode (401a - 401e) and the first detecting electrode (401a - 401e), and between the second applying electrode (403a - 403e) and the second detecting electrode (403a - 403e); and a detecting unit configured to obtain a first response signal detected by the electric current detection circuit of the first sensor and a second response signal detected by the electric current detection circuit of the second sensor, and to detect whether a foreign object is adhered to the piece of paper or the piece of paper has folds from a result of comparing the first response signal with the second response signal, wherein the first applying electrode (401a - 401e) and the second applying electrode (403a - 403e) are arranged on opposite sides of the conveyance path (a) and the first detecting electrode (401a - 401e) and the second detecting electrode (403a - 403e) are arranged on opposite sides of the conveyance path (a). a first sensor including a first applying electrode (401a - 401e) and a first detecting electrode (401a - 401e) that are opposed to each other, the first sensor being coupled to an electric current detection circuit for detecting electric current in the first detecting electrode (401a - 401e) based on a change in electrostatic capacitance when a piece of paper passes between the first applying electrode (401a - 401e) and the first detecting electrode (401a - 401e); a second sensor including a second applying electrode (403a - 403e) and a second detecting electrode (403a - 403e) that are opposed to each other, the second sensor being coupled to an electric current detection circuit for detecting electric current in the second detecting electrode based on a change in electrostatic capacitance when a piece of paper passes between the second applying electrode (403a - 403e) and the second detecting electrode (403a - 403e); a conveyance path (a) configured to convey the piece of paper between the first applying electrode (401a - 401e) and the first detecting electrode (401a - 401e), and between the second applying electrode (403a - 403e) and the second detecting electrode (403a - 403e); and a detecting unit configured to obtain a first response signal detected by the electric current detection circuit of the first sensor and a second response signal detected by the electric current detection circuit of the second sensor, and to detect whether a foreign object is adhered to the piece of paper or the piece of paper has folds from a result of comparing the first response signal with the second response signal, wherein the first applying electrode (401a - 401e) and the second applying electrode (403a - 403e) are arranged on opposite sides of the conveyance path (a) and the first detecting electrode (401a - 401e) and the second detecting electrode (403a - 403e) are arranged on opposite sides of the conveyance path (a).