Aim — to improve phacoemulsification technique of mature intumescent cataract and to study mechanisms of possible uncontrolled tearing of the anterior lens capsule during creation of the anterior capsulorhexis. Material and methods. Two groups were formed. Group 1 consisted of 52 patients with mature intumescent cataract, in whom a two-stage capsulorhexis was performed with lenticular masses removed from the anterior and posterior capsular bag compartments in between the two stages. Group 2 consisted of 55 patients with mature intumescent cataract, whose capsulorhexis was standard. Results. We have specified appropriate methods for diagnosing intumescent cataract and thoroughly investigated the mechanism of uncontrolled tearing of the anterior capsule that can occur during creation of the anterior capsulorhexis. Five structural variants of the swollen lens have been described. As to surgical complications, there were 2 cases (3.8%) of small anterior capsulorhexis tearing in group 1 that were managed by converting the capsulorhexis into the a bigger one and, thus, did not affect surgical outcomes. In group 2, there were 7 cases of uncontrolled tearing of the anterior capsule during creation of the anterior capsulorhexis, in 4 of them (7,3%) the posterior capsule got also involved. Conclusion. 1. It has been found that on ultrasound biomicroscopy, mature intumescent cataract is notable for a 10—15° wider equatorial angle as compared to the fellow eye, which can be regarded as spherophakia. 2. Five different structural variants of the swollen opaque lens have been described. 3. The mechanism of uncontrolled tearing of the anterior capsule during creation of the anterior capsulorhexis has been studied and the expediency of two-stage capsulorhexis with lenticular mass removal from capsular bag compartments proved.