Background: Robot-assisted gait training (RAGT) is widely used to improve gait function in children with cerebral palsy (CP). Exoskeleton and end-effector type robots provide different mechanical assistance; however, their immediate effects on plantar pressure distribution and gait speed have not been directly compared. Objects: This study compared the immediate effects of a single session of two robot types of RAGT on plantar pressure distribution and gait speed in children with spastic CP, and examined associations between changes in plantar pressure and gait speed. Methods: Twelve children with spastic CP (4–18 years; Gross Motor Function Classification System I–III) participated in a randomized cross-over design. Each participant completed one 30-minute session of exoskeleton- and end-effector type RAGT with a washout period of ≥ 2 days. Gait speed was assessed using the 10-meter walk test (10MWT), and plantar pressure was measured using the GaitView® system. Outcomes included symmetry ratio (SR), more affected side plantar pressure ratio (MAPR), and more affected side forefoot and rearfoot plantar pressure ratios (MAFPR and MARPR). Robot type effects were examined using two-way repeated-measures analysis, within-robot pre–post changes using paired t-tests, and associations using Pearson correlation coefficients (α = 0.05). Results: No significant main or interaction effects of robot type were found for 10MWT, SR, MAPR, MAFPR, or MARPR (all p > 0.10). Within-robot analyses showed significant reductions in 10MWT and SR and significant increases in MAPR following both interventions (p < 0.05). A significant increase in MARPR was observed only after exoskeleton type RAGT. Changes in gait speed were associated with changes in MAPR in the exoskeleton type condition (r = 0.587, p = 0.045), whereas no significant correlations were observed in the end-effector type condition. Conclusion: Although no significant between-robot differences were observed, exoskeleton and end-effector type robots demonstrated distinct within-robot changes in plantar pressure distribution following a single session of RAGT.