An apparatus for producing recycled pellets, comprising: a loss film supply section configured to bundle one or more loss films of thermoplastic resin into a predetermined width, and supply a resultant loss film bundle to an intermediate feed section; the intermediate feed section configured to send out the supplied loss film while sandwiching the supplied loss film, the intermediate feed section serving as a starting point of twisting of the loss film; and a rotary compression section configured to be supplied with the loss film from the intermediate feed section, and configured to rotate relatively to the intermediate feed section to twist the loss film, take up the loss film faster than a sending speed of the intermediate feed section to apply a stretch to the loss film, and send out a twisted string, the apparatus (A1, A2, A3) being configured to produce recycled pellets by cutting the twisted string sent out from the rotary compression section, at a predetermined length, wherein a first heating section configured to preheat the loss film at the softening temperature of the loss film is disposed between the loss film supply section and the intermediate feed section, characterised in that the first heating section comprises: a heating section body configured to reciprocate between a heating position that surrounds a movement line of a loss film bundle to be preheated, and a retracted position out of the heating position, the heating section body having an opening that is a gate for the loss film to be preheated during the reciprocation, the opening being formed over the entire surface of the heating section body on a moving direction side; an opening/closing lid configured to close the opening at the time of heating to form a heating space inside for the loss film; and a hot air supplying part configured to supply the heating space with hot air. a loss film supply section configured to bundle one or more loss films of thermoplastic resin into a predetermined width, and supply a resultant loss film bundle to an intermediate feed section; the intermediate feed section configured to send out the supplied loss film while sandwiching the supplied loss film, the intermediate feed section serving as a starting point of twisting of the loss film; and a rotary compression section configured to be supplied with the loss film from the intermediate feed section, and configured to rotate relatively to the intermediate feed section to twist the loss film, take up the loss film faster than a sending speed of the intermediate feed section to apply a stretch to the loss film, and send out a twisted string, the apparatus (A1, A2, A3) being configured to produce recycled pellets by cutting the twisted string sent out from the rotary compression section, at a predetermined length, wherein a first heating section configured to preheat the loss film at the softening temperature of the loss film is disposed between the loss film supply section and the intermediate feed section, characterised in that the first heating section comprises: a heating section body configured to reciprocate between a heating position that surrounds a movement line of a loss film bundle to be preheated, and a retracted position out of the heating position, the heating section body having an opening that is a gate for the loss film to be preheated during the reciprocation, the opening being formed over the entire surface of the heating section body on a moving direction side; an opening/closing lid configured to close the opening at the time of heating to form a heating space inside for the loss film; and a hot air supplying part configured to supply the heating space with hot air. a heating section body configured to reciprocate between a heating position that surrounds a movement line of a loss film bundle to be preheated, and a retracted position out of the heating position, the heating section body having an opening that is a gate for the loss film to be preheated during the reciprocation, the opening being formed over the entire surface of the heating section body on a moving direction side; an opening/closing lid configured to close the opening at the time of heating to form a heating space inside for the loss film; and a hot air supplying part configured to supply the heating space with hot air.