Although surgical decompression of the involved spinal cord achieves a good recovery of neurological conditions, one of the most important complaints of patients with ossification of the posterior longitudinal ligament (OPLL) is disability as a result of spinal immobility. The activities of daily living (ADL) of postoperative patients with OPLL were examined. To evaluate the ADL of postoperative patients with OPLL in the cervical spine, we utilized the Bath Ankylosing Spondylitis Functional Index (BASFI), one of the most widely used functional indexes for ankylosing spondylitis. We investigated consecutive cases that underwent surgery for OPLL of the cervical spine in our department from 1978 to 1998. The latest and postoperative scores were compared to the preoperative Japanese Orthopaedic Association (JOA) scores (range, 0-17) to assess neurological recovery. We also evaluated ADL at the latest follow-up, using BASFI scores. Significant recoveries of JOA scores were confirmed; however, 77% of patients complained of disability. In BASFI, questions that seemed to reflect spinal condition received low scores in the present study. BASFI scoring was not sufficient in the present form; however, it is one of the candidate functional indexes for evaluating ADL in postoperative patients with OPLL. Establishment of an ideal functional index for such evaluation is needed.