Arteriovenous malformations of the lung are rare pulmonary vascular disorders which can suddenly lead to life threatening complications. Haemothorax due to rupture of a pulmonary arteriovenous malformation (PAVM) is very rare. We report here a case of a 39 year-old lady who presented with an acute onset of shortness of breath due to right-sided massive haemothorax and was subsequently detected to have pulmonary as well as cerebral arteriovenous malformation (CAVM).