This research aims to provide insight for web form design for older users. The effects of task complexity and information structure of web forms on older users' performance were examined. Forty-eight older participants with abundant computer and web experience were recruited. The results showed significant differences in task time and error rate among three levels of task complexity. Significant differences were also found in older users' disorientation among four levels of information structures. The results indicated that the "decision complexity advantage" may not be applicable to older users because of age-related functional impairment. (Contains 5 tables.)