Objective To compare the clinical efficacy of radial extracorporeal shock wave therapy （rESWT） applied with the ankle in different positions for treating triceps surae spasticity after stroke， and to provide evidence for optimizing treatment protocols. Methods A prospective， randomized， single-blind （assessor-blinded）， controlled design was employed. A total of 58 patients admitted to the hospital between June 2023 and December 2024 were enrolled and randomly assigned to either the experimental group （n = 29， ankle dorsiflexion position） or the control group （n = 29， ankle relaxation position）. Both groups received conventional rehabilitation therapy combined with extracorporeal shock wave treatment. Assessments were conducted at four time points： before treatment initiation （T₀）， on the final day of treatment （T₁）， at 2 weeks post-treatment （T₂）， and at 4 weeks post-treatment （T₃）. The outcome measures included the Composite Spasticity Scale （CSS） for the ankle， 10-Meter Walk Test time （10MWT）， step frequency， the Modified Ashworth Scale （MAS）， passive range of motion （PROM） of the ankle， and the Fugl-Meyer Assessment for lower extremity motor function （FMA-L）. Results The comparative analysis of intervention effects between the experimental and control groups revealed the following key findings： （1）CSS scores decreased significantly over time， with the experimental group showing markedly lower scores than the control group at both mid-term （T₂） and late-term （T₃） assessments （P < 0.01）， and a greater overall improvement （5.65 points vs. 3.17 points， P = 0.003）. （2）The 10MWT results demonstrated a consistent improving trend in both groups， although the experimental group performed significantly better than the control group at T₂ （P < 0.01）， with a more pronounced overall improvement （7.76 s vs. 6.38 s）. （3）Step frequency increased over time， with the experimental group exhibiting higher values than the control group at both T₂ and T₃ （P < 0.05）， and a greater magnitude of improvement （15.41 steps/min vs. 11.31 steps/min）. （4）MAS scores indicated that spasticity relief in the experimental group was superior to that in the control group during the early and mid-term phases （T₁， T₂） （P < 0.01）； however， the control group showed lower scores at T₃ （P < 0.05）. （5）PROM assessment revealed that ankle dorsiflexion range of motion improvement in the experimental group was significantly better than that in the control group at all time points （all P < 0.001）， with a greater overall increase （7.65° vs. 4.76°）. （6）FMA-L scores similarly demonstrated that motor function in the experimental group was superior to that in the control group at all assessed time points （all P < 0.001）， with a larger overall improvement （1.62 points vs. 0.55 points）. Conclusions rESWT combined with conventional rehabilitation effectively alleviates ankle spasticity and improves gait and motor function in post-stroke patients. Administering rESWT with the ankle in a dorsiflexed position yields superior therapeutic effects on a comprehensive set of functional outcomes compared to a relaxed ankle position. Therefore， the dorsiflexion position is recommended as the preferred posture for clinical application of rESWT in this patient population.