Otitis media with effusion (OME) is the most frequent illness in children. Surgical treatment options include ventilation tube insertion, adenoidectomy or both. Opinions regarding the risks, benefits and intubation period of ventilation tube insertion vary greatly. To determine the appropriate time for when to remove asymptomatic longterm ventilation T-tubes in children. In this prospective study, we analyzed the results of 120 pediatric patients (6-12 years) (240 ears) with persistent OME; we employed the Goode T-silicone tubes. We intentionally planned to remove the tubes at different time points of the study and divided our patients randomly into four subgroups with 30 patents (60 ears in each) according to the intubation period; group I: intubation for 6 months, group II: intubation for 12 months, group III: intubation for 18 months and group IV: intubation for 24 months. The relationship between intubation period and OME recurrence, the rate of persistent tympanic membrane (TM) perforation, granulation tissue or discharge near the tympanostomy tubes, normalization of Eustachian tube function and change of hearing level was analyzed in each patient group. The χ analysis showed that the rate of normalization of ET function was significantly higher when tubes were removed after 12-months of intubation (P = 0.002), the rate of OME recurrence was significantly higher when tubes were removed before 12-months of intubation (P = 0.004), The rate of otorrhea significantly increased after 12-months of intubation, development of granulation around tubes was significantly higher after 18-months of tube insertion. The rate of appearance of permanent TM perforation significantly increased after 18-months from tube insertion (P = 0.008). Adenoidectomy did not significantly influence the recurrence rate of OME or the rate of persistent TM peroration after tube removal. Our present results suggest that the appropriate intubation period for healing OME in children would be at 12-18 months. Also, we can conclude that longterm ventilation tubes are recommended to avoid repeated intubation and to obtain sufficient results, although their performance is not always satisfactory; mainly because of accompanying complications.