Hamstring muscle length may be associated with specific pelvic and trunk postures, but the influence of hamstring length on trunk postures is not well documented. The purposes of this study were to examine the influence of hamstring length on 1) the pelvic angle, lumbar angle, and thoracic angle in standing; and 2) the flexion ranges of motion of the pelvic angle, lumbar angle, and thoracic angle during the toe-touch test. Surface platform pointers over bony landmarks and photography were used to examine the pelvic and trunk angles and ranges of motion of 10 men with short hamstrings, 10 men with medium hamstrings, and 10 men with long hamstrings while standing and after assuming the toe-touch position. Separate one-way analyses of variance detected no significant differences among groups for the three angles in standing. Significant differences were detected among groups for the three angles in the toe-touch position and the flexion ranges of motion during the toe-touch test (p < 0.05). Short hamstrings were associated with decreased flexion range of motion of the pelvic angle and lumbar angle and increased flexion range of motion of the thoracic angle. Therapeutic interventions should be considered in light of the influences of hamstring length on the flexion range of motion of the pelvic angle, lumbar angle, and thoracic. angle.