Flexible polyurethane (PUR) foam was chemically recycled using two types of oleochemical polyols based on rapeseed oil and waste fish oil. The functional hydroxyl groups of the oleochemical polyols reacted with the urethane and the disubstituted urea structures of flexible PUR foam at temperatures around 200 °C. The liquid recycled polyols with hydroxyl numbers ca. 175 mg KOH/g were obtained after 2 h of the reaction. Only the recycled polyols without additional virgin polyols were used for the preparation of low density PUR foams. PUR foams with free rise density of 30 and 50 kg/m3 were prepared exhibiting semi-rigid character due to the presence of soft segments of fatty acid chains.