Objective The contrast observation on the eye axis length cheange between 3-7years odl children after congenitial cataract surgery with Ⅱ stage intraoular lens implantation and heathy (normal)peers children.Methods To retrospectively collect 26cases (42eyes) of the 3-7 years odl children who accept congenital cataract treatwent with Ⅱ period artificial lens implanted from October 2005to October 2012 in our line To record the shalft length of the eyes a when the Ⅱ stage intraocular lens is implanted in the eye as a research group and the contrast group is to colleet 28cases of 3-7 years old Children with traumatic cataract fron october 2003 to october 2012 and then have a contrast observation for their eye axis length.Results The eye axis length of the 3-7 yeara old children after the congenital cataract surgery with Ⅱ stage intraocular lens implanted grows more fast than the same age norml children;The coonparison has an obvious difference (P ＜0.05).Conclusions The eye axis length q of the 3-7 years old children without implanting Ⅱ stage intraocular lens in the early congenital cataract surgery obriously grows more fast than same age normal children.And then it guides us to implant the intraocular lens for the congenital cataract children as early as possible to prevent and reduce the series of pwblem that is caysed due to the abnormal growth of the eye axis.