PURPOSE: Cerebral Palsy (CP) is the commonest cause of childhood motor disability. Transcranial direct current stimulation (tDCS) is a promising adjuvant therapy, but research targeting upper and lower limbs simultaneously is needed. We aimed to pilot tDCS with upper/lower limb motor training, estimate the potential effect on motor function, and investigate brain imaging correlates of function. MATERIALS AND METHODS: Participants (10-16 years) with CP affecting upper and/or lower limbs were randomised (online software) to 10 sessions of active (n = 14) or sham (n = 13) tDCS combined with motor training. The primary outcomes were upper and lower limb function assessed at 1-week post-intervention using the Jebson Taylor hand function (JTT) and Timed Up and Go (TUG) tests. Secondary, imaging outcomes included baseline tractography, grey matter volume, and resting state connectivity. RESULTS: Adherence was good: 74% completed all intervention sessions, 100% completed the primary outcome assessment. There were no between-group differences (1-week post-intervention, intention-to-treat; group-by-time JTT: F(1,25)=1.189,p = 0.286, partial-eta-squared = 0.05; TUG: F(1,25)=1.605,p = 0.217, partial-eta-squared = 0.06). Imaging showed subtle associations between better JTT at baseline and higher grey matter volume (caudate nucleus) and stronger sensorimotor resting state connectivity. CONCLUSIONS: The trial was well tolerated, but effect sizes were small. Larger studies are needed to further explore tDCS for CP.