We analyzed mechanical tensile properties of 16 10-mm wide, full-thickness central parts of quadriceps tendons and patellar ligaments from paired knees of eight male donors (mean age, 24.9 years). Uniaxial tensile testing was performed in a servohydraulic ma- terials testing machine at an extension rate of 1 mm/ sec. Sixteen specimens were tested unconditioned and 16 specimens were tested after cyclic precondi- tioning (200 cycles between 50 N and 800 N at 0.5 Hz). Mean cross-sectional areas measured 64.6 ± 8.4 mm² for seven unconditioned and 61.9 ± 9.0 mm² for eight preconditioned quadriceps tendons and were signifi- cantly larger than those values of seven unconditioned and seven preconditioned patellar ligaments (36.8 ± 5.7 mm² and 34.5 ± 4.4 mm², respectively). Mean ultimate tensile stress values of unconditioned patellar ligaments were significantly larger than those values of unconditioned quadriceps tendons: 53.4 ± 7.2 N/mm² and 33.6 ± 8.1 N/mm², respectively. Strain at failure was 14.4% ± 3.3% for preconditioned patellar liga- ments and 11.2% ± 2.2% for preconditioned quadri- ceps tendons (P = 0.0428). Preconditioned patellar ligaments exhibited significantly higher elastic modulus than preconditioned quadriceps tendons. Based on mechanical tensile properties analyses, the quadriceps tendon-bone construct may represent a versatile alter- native graft in primary and revision anterior and poste- rior cruciate ligament reconstruction.