Parotid sialocele is a challenging complication following major salivary gland surgery. Traditional conservative management often fails, while revision surgery carries a high risk of iatrogenic facial nerve injury. This retrospective, single-center case series evaluated the clinical efficacy and safety of ultrasound-guided Botulinum Toxin Type A (BoNT-A) infiltration in eight consecutive patients presenting with post-surgical parotid sialoceles. The protocol comprised complete ultrasound-guided evacuative aspiration followed by intraglandular injections of OnabotulinumtoxinA into functional parenchyma using a standardized grid mapping technique. Dosage was individualized based on the sonographic estimation of the residual volume of glandular tissue. Post-procedure care included a soft diet, temporary avoidance of sialagogues, and strict avoidance of local massage for 24 h. Complete clinical and sonographic resolution was achieved in all 8 treated cases within a mean interval of 10 days post-injection. Follow-up at 3 months confirmed no recurrences or late-onset complications. No local or systemic adverse events were recorded. In this preliminary case series, ultrasound-guided intraglandular BoNT-A injection represented a safe and encouraging minimally invasive second-line option for post-surgical parotid sialoceles.