The authors aimed to compare the visual outcomes of primary and secondary IOL implantation and to identify the risk factors for the development of strabismus in patients with paediatric cataract. The study included 220 eyes of 148 patients: 76 unilateral and 72 bilateral cataracts. Primary posterior chamber IOL implant was in 180 eyes and secondary in 40 eyes (ciliary sulcus in 16, scleral-fixated in 24). Mean age at surgery was 6.84±3.45 years for primary implant and 8.92±5.12 years for secondary. Mean interval from primary cataract surgery to secondary was 4.54±4.27 years. At final follow-up mean best corrected visual acuity (BCVA) was 0.44±0.33 logMAR in primary and 0.28±0.32 in secondary implant. Ten percent of the primary group had stereopsis and fusion postoperatively versus none for secondary. Strabismus was present in 24 for primary and 30% for secondary implant. Nystagmus was present in 9% for primary and 20% for secondary. Possible risk factors found for development of strabismus and visual acuity included lower visual acuity causing more strabismus. The authors conclude optical rehabilitation is a key factor for potential development of strabismus in paediatric cataract.