Background:　The　use　of　external　fixators　to　treat　foot　and　ankle　deformities　remains　a　challenge　in　orthopedic　surgery　due　to　their　diversity.　We　hope　to　improve　the　automation　and　accuracy　of　the　correction　process.　Methods:　A　three-degree-of-freedom　(3-DOF)　electromotor-driven　external　fixator　for　uniplanar　foot　and　ankle　deformities　was　proposed.　Computer-assisted　correction　software　was　developed　to　help　surgeons　use　digital　technology　to　measure　the　required　parameters　from　patients＇　X-ray　radiographs.　The　correction　trajectory　and　the　prescriptions　were　generated　in　the　software　based　on　the　proposed　correction　strategy.　Results:　Two　clinical　cases　were　simulated　to　verify　the　correction　ability　of　the　developed　external　fixator.　The　results　showed　that　the　angular　and　displacement　deformities　were　well　corrected.　Conclusions:　The　developed　external　fixator　can　accurately　and　automatically　correct　foot　and　ankle　deformities　with　the　help　of　computer-assisted　correction　software,　which　significantly　reduces　the　burden　on　surgeons　and　patients.　©　2023　John　Wiley　&　Sons　Ltd.