AIM: To compare the incidence of intraoperative complications during primary phacoemulsification (phaco) surgery between resident surgeons (residents) and staff surgeons (specialists) and to objectively determine the difficulty of stages in phaco surgery. METHODS: This retrospective study included cases of phaco cataract surgery performed between January and December 2019. There were no exclusion criteria. For each patient, demographics, clinical history, case complexity, type of surgeon, and operative details were reviewed. Primary outcomes included intraoperative complication rates and the objective measure of difficulty in the steps of the surgery performed by residents and specialists. RESULTS: A total of 3272 cases were included; 7.4% (n=241) of cases were performed by residents. The overall complication rate was 5.4% (n=177). The intraoperative complication rate was significantly higher (P<0.001) in residents (n=33, 13.7%) than in specialists (n=144, 4.8%). The most frequent complications were posterior capsule tear (n=85, 2.6%), anterior capsule tear (n=50, 1.53%), zonular fiber loss (n=45, 1.38%), and dropped nucleus (n=15, 0.46%). Objectively, the most difficult steps during surgery were phaco in 66 (60.0%), capsulorhexis in 21 (19.1%), irrigation/aspiration in 13 (11.8%), hydrodissection in 9 (8.2%), and intraocular lens (IOL) implantation in 1 (0.9%) case. CONCLUSION: Intraoperative complication rates are higher in residents than in specialists. The order of objective difficulty in phaco surgery steps is in line with the subjective findings of other surveys, revealing that the most challenging parts of phaco surgery are phaco and capsulorhexis.