Little is known about the responses to graded exercise in athletes with cerebral palsy (CP). This study compared the ventilatory threshold (VT) and peak VO₂ among athletes with CP during treadmill and cycle ergometry exercise. Six (4 men, 2 women) track athletes with CP volunteered to participate in the study. Graded exercise tests on a treadmill and cycle ergometer were performed on separate days to assess VT and peak VO₂. Paired t tests were used to compare the two exercise modes. The VT, expressed as a percentage of peak VO₂, was significantly higher on the cycle ergometer than on the treadmill. The absolute VO₂ at the VT was similar during both testing modes, and peak VO₂ was significantly higher on the treadmill than on the cycle ergometer. Similar to responses seen in able-bodied individuals, the VO₂ at VT was similar during both modes of exercise, while the peak VO₂ was 10% lower on the cycle than on the treadmill. Cycle ergometer peak VO₂ in these athletes was higher than previous reports of individuals with CP for the cycle ergometer.