This study used waste chicken fat oil (CFO) to regenerate aged asphalt binder. The molecular composition of the CFO was assayed by gas chromatography-mass spectrometry. The performance grade of the CFO-rejuvenated recycled asphalt was compared with that of the original asphalt, while the high-temperature rutting performance of CFO-rejuvenated asphalt was assessed by the multiple stress creep recovery test, and the fatigue cracking ability of the rejuvenated asphalt was determined by a linear amplitude sweep test. It is obvious that CFO can soften aged asphalt. The performance grade of low-temperature 6% CFO-rejuvenated asphalt is superior to that of the original asphalt. The sulfoxide index can be utilised to evaluate the aging recovery degree of CFO-rejuvenated asphalt. The addition of CFO can improve the fatigue properties of aged binder and delay the fatigue damage of asphalt. It is suggested that 6% CFO should be used in recycling aged asphalt binder.