A mucous cyst is a benign, self limiting mucous containing cyst of the salivary glands commonly occuring in the oral cavity. Mucocele may develop following the obstruction of the salivary flow from secretory apparatus of the salivary gland. Mucoceles commonly occur on the lower lip but may occur in other locations too. The objective of the study was to determine the factors associated with mucocele in patients attending the dental clinic of Penang Hospital from January 2000 to December 2005. This is a retrospective record review analysis of all the total 35 cases treated during this period, comprising of 20 males (57.1%) and 15 females (42.9%) with Malays as the largest group of patients treated and, mainly students had seek treatment. Mucocele was frequently treated in patients aged 21 to 24 year old. The site of the mucocele was the lower lip and all of the cases were treated surgically. The size of the mucocele ranged from 0.5 to 5 centimetres with 1.0 cm as the most common size. Most of the patients gave a history of spontaneous development (71.4%), followed by lip biting (25.7%) and trauma (2.9%). Lip biting was more common among students (55.6%) as compared to others. There were only two recorded cases of recurrence.