The purpose of this retrospective clinical study was to assess the clinical outcomes of a group of patients who underwent arthroscopic infrapatellar plica (IPP) excision, to determine whether the IPP was symptomatic or not, and the symptoms or signs in the patient’s clinical presentation and correlations between arthroscopic findings and the patient’s clinical presentation. We studied all patients undergoing arthroscopic resection of symptomatic IPP without other intraarticular abnormality at our department from February 1996 to April 2001. Fourteen patients with isolated IPP and with regular follow-up intervals were included. Arthroscopy findings, preoperative magnetic resonance imaging (MRI) findings, and clinical presentation were correlated. The mean duration of follow-up was 36 months with a range of 24–60 months. The IPP was found to be in a fenestra pattern in seven patients, separate (cordlike) pattern in five patients, and vertical septum pattern in two patients. IPP in all patients was excised with a powered instrument. Excellent and good results were obtained in 12 (89%) patients. Two patients had poor results. All patients had been documented as having pain; popping, or snapping with flexion and extension; giving way; and swelling. There was no correlation between IPP type and MRI findings with being symptomatic (p>0.05). It was found that IPP type was not a prognostic factor (p>0.05). IPP should be considered as a possible cause of knee pain when MRI imaging exhibits no other internal derangement.