Objectives: This study aimed to assess the effects of botulinum toxin A (BTX-A) infiltration on face muscle function, synkinesis, and quality of life in patients with sequelae of peripheral facial palsy (PFP)., Material and Methods: We present the results of a prospective study including a sample of 20 patients with sequelae of PFP (15 women, 5 men) who underwent BTX-A (Botox© or Xeomin©) infiltration. All patients had previously received personalised treatment with neuromuscular retraining. A clinical assessment was performed before BTX-A infiltration and 4 weeks after treatment. The effect of BTX-A on face muscle function, quality of life, and synkinesis was evaluated using the Sunnybrook Facial Grading System (SFGS), the Facial Clinimetric Evaluation (FaCE) questionnaire, and the Synkinesis Assessment Questionnaire (SAQ), respectively., Results: Mean SFGS scores increased from 64.8 to 69.9 after BTX-A infiltration (P=.004). Increases were also observed in mean total FaCE scores (from 52.42 to 64.5; P<.001) and the mean score on the FaCE social function subscale (from 61.15 to 78.44; P<.001). Mean SAQ scores decreased from 46.22 to 37.55 after BTX-A infiltration (P=.001)., Conclusions: BTX-A infiltration increases face muscle function, improves quality of life, and reduces synkinesis in patients with sequelae of PFP., (Copyright © 2021 Sociedad Española de Neurología. Published by Elsevier España, S.L.U. All rights reserved.)