Purpose: There are a lot of reports that mumps has reemerged in spite of vaccination. I would like to know its recent clinical features and propose measures for it. Methods: I collected the clinical informations of mumps patients who had been diagnosed at the Department of Pediatrics , YongIn Severance Hospital, YongIn, Korea from January 2009 to December 2010 by clinical evidence. Their clinical data were investigated. Results: There were 32 mumps cases for 2 years . Twenty cases (62.5%) were over 13 years old and found from March to April. Male to female ratio were 1.3:1. About one third of all patients(31.2%) had mumps vaccination twice. All patients showed parotid gland swelling. Other clinical features were fever (53.1%), chill (46.9%), myalgia (40.6%), cough (25%) and headache (18.7%). There was one meningitis case (3.1%). Their clinical symptoms were resolved within 10 days. No complication except meningitis was found. Conclusion: Mumps is not rare during spring among teens lately in spite of current vaccination policy. Continuous monitoring for it is needed and modification of its vaccination schedule should be considered.