OBJECTIVE: To compare the efficacy of the innervation zone-targeted injection technique (EUROMUSCULUS/USPRM (Ultrasound Study Group of the International Society of Physical and Rehabilitation Medicine) spasticity approach) and the injection technique along the muscle length. DESIGN: A double-blind randomized controlled trial. SETTING: Department of rehabilitation medicine of a medical center. PARTICIPANTS: One hundred patients with stroke experiencing ankle plantar flexor spasticity. INTERVENTIONS: In addition to conventional rehabilitation, eligible patients were randomly assigned to 2 groups. The experimental group was injected with botulinum toxin along the length of the muscle, whereas the control group was injected with the same dose and volume of botulinum toxin 25%-35% proximal to the medial head and 20%-30% proximal to the lateral aspect of the head of the gastrocnemius muscle. MAIN OUTCOME MEASURES: Modified Ashworth scale, modified Tardieu scale, ankle range of motion measurement, and 10-meter walk test were used before and 1 month after injection. RESULTS: The study was completed by 60 participants with a mean age of 59.96±12.15 years. Both injection methods were found to be effective on range of motion, spasticity level, ambulation, and walking speed. There was no statistically significant difference between injection methods. CONCLUSIONS: Both injection methods of botulinum toxin A produce similar clinical effects.