Purpose <p>To evaluate the incidence and risk factors for cataract following pediatric pars plana vitrectomy (PPV).</p> Setting <p>Tertiary referral center.</p> Design <p>Retrospective consecutive case series.</p> Methods <p>We included 242 eyes of 218 patients (&lt; 18 years) that underwent lens-sparring PPV with a minimum follow-up of 6 months. Information regarding demographic and ophthalmic features, surgical history and procedures were gathered and analyzed. Eyes were evaluated for the development of cataract requiring surgery.</p> Results <p>Mean age at surgery was 6.8 ± 5.0 years and mean follow-up was 31.9 ± 37.5 months. After a mean interval of 17.0 ± 22.0 months, 80 eyes (33.1%) required lensectomy with posterior subcapsular cataract being the most common cataract type (76.3%). Overall, the risk of developing cataract after PPV increased from 21% at 1 year to 47% at 5 years The factor associated with the development of postoperative cataract were the need for multiple surgeries (58.8% vs. 13.6%, <i>p</i> &lt; 0.001), the type of tamponade used <i>p</i> &lt; 0.001), older age at surgery (101.9 ± 53.1 months vs. 71.0 ± 60.8 months, <i>p</i> &lt; 0.001), and retinal detachment (78.8% vs. 19.1%, <i>p</i> &lt; 0.001). Multivariate analysis including the aforementioned variables identified the need for multiple surgeries [OR: 2.7 (CI: 1.2–6.2), <i>p</i> = 0.02)] as a risk factor for the development post-PPV cataract while the use of air or no tamponade as protective (<i>p</i> = 0.001).</p> Conclusions <p>Post-PPV cataract is a common complication occurring in about one-third of children. Risk factors include silicone oil tamponade, gas tamponade and multiple surgeries. Follow-up should be started early and continued for an extended duration after PPV especially in young children at risk of developing amblyopia.</p>