STUDY DESIGN: Retrospective study. OBJECTIVES: To investigate radiologic and clinical outcomes of teriparatide in women with osteoporosis after instrumented lumbar posterolateral fusion (PLF) or posterior lumbar interbody fusion (PLIF). SUMMARY OF LITERATURE REVIEW: Teriparatide accelerated lumbar posterolateral fusion in women with postmenopausal osteoporosis. MATERIALS AND METHODS: Eighty-six women older than 65 years old with osteoporosis underwent PLF or PLIF with bone graft between Februar, 2011 ato May, 2012 pPatients were divided into four group: teriparatide group with local bone (A-1: 13 patients;, teriparatide group with composite bone (A-2: 27 patients; non-teriparatide group with local bone (B-1: 14 patients; and non-teriparatide group with composite bone (B-2: 32 patients). At 3, 6, and 12 months postoperatively, the Oswestry Disability Index (ODI), visual analog scale (VAS), fusion rate, and period of bone union were evaluated. RESULTS: VAS and ODI improved after surgery in all groups, but no significant differences were notell among the groupses Further, there was no significant difference among the groups for agef fusion level, and fusiops(p>0.05). Fusion rate was 94.44% in the A-1 group, 92.59% in the A-2 group, 79.17% in the B-1 group, and 76.92% in the B-2 group. Average period of bone union was 3.25 months, 3.65 months, 5.67 months, anand 5.65 months respectively. Fusion rate and average bone union time made no significant differeneen among the groups divided by graft materials (p>0.05). However, those in the teriparatide group were significantly superior to those in the non-teriparatide group (p<0.05). CONCLUSIONS: In women with osteoporosis after PLF or PLIF with bonegraft, teriparatide showed superiority in the rate of fusion and the period of bone union.