Introduction: Acute Necrotising Sialometaplasia (ANSM) is a benign, rare and self-limiting inflammatory condition of salivary gland tissue which classically presents as a unilateral necrotic ulcer on the hard palate. The primary aetiology is trauma of minor salivary gland tissue which has been reported to occur following local anaesthetic infiltrations, surgery, heavy smoking, excessive alcohol consumption and violent vomiting such as in patients with bulimia. The most significant issue is that is may, both clinically and histologically, mimic malignancy which could potentially result in an incorrect diagnosis and unnecessary treatment. ANSM is self- limiting and usually heals spontaneously between 3-12 weeks without complication. Case description: A 43-year-old Caucasian female was referred to the Oral and Maxillofacial Surgery department by her general practitioner following an eight-day history of a painful ulcer on the hard palate. Her medical history was unremarkable, and she was a non-smoker with a low alcohol consumption. On examination, there was a 1.0x1.5cm diameter 'punched out' ulcer on the left posterior hard palate which extended down to bone. An urgent incisional biopsy was undertaken which con- firmed a diagnosis of ANSM and excluded dysplasia. The patient was reassured and subsequently discharged at an eight-week review following resolution of the lesion. Results and conclusion: ANSM can present a diagnostic dilemma as it mimics malignancy both clinically and histologically. It is therefore vital that practitioners have an awareness of the condition and appreciate its benign and self-limiting nature to avoid unnecessary surgical intervention and patient distress. An urgent referral to a specialist in Oral and Max- illofacial Surgery or Oral Medicine is vital such that an incisional biopsy can be undertaken to confirm a diagnosis and exclude malignancy. Take-home message: Clinicians should be aware of ANSM and understand the importance of an urgent referral to a specialist to exclude malignancy.