In the present study, we aimed to demonstrate the objective guiding role of objective scatter index (OSI) in patients with early stage posterior capsule opacification (PCO), especially in patients with multifocal intraocular lens (IOL) implantation. A prospective randomized case analysis was conducted on elderly patients experiencing PCO, exhibiting best-corrected visual acuity (BCVA) below 0.2 LogMAR. Exclusion criteria comprised patients with diabetes, glaucoma, high myopia, trauma, endothelial dystrophy, maculopathy or prior eye surgery affecting visual acuity. The main observational indicators were patient gender, age, post-cataract surgery duration, BCVA (LogMAR), and OSI values. For patients undergoing laser posterior capsulotomy, meticulous documentation of pre-laser OSI values and post-laser OSI values was undertaken. Subjective visual quality was then compared using the Chinese version visual function index-14 (VF-14-CN). The study comprised 65 eyes from 56 patients. PCO developed, on average, 2.06 ± 0.94 years (ranging from 0.5 to 4 years) after the initial surgery, with the OSI consistently exceeding 3.0. Among these cases, only 40 eyes underwent laser posterior capsulotomy using Nd:YAG laser, including 26 eyes implanted with monofocal IOLs and 14 eyes implanted with multifocal IOLs. Following laser posterior capsulotomy for early-stage secondary cataracts, there was a significant decrease in OSI values compared to the presurgery state, coupled with a notable increase in VF-14-CN scores. Among the 14 cases with multifocal IOL implantation, pre-laser VF-14-CN scores were lower compared to those with monofocal IOLs. Post-laser posterior capsulotomy, patients reported a marked improvement in self-perceived symptoms. The OQAS functioned as an objective assessment metric for the laser treatment of early stage PCO. In cases involving multifocal IOL implantation, the visual disturbance caused by PCO was more pronounced, underscoring the significance of OSI as a valuable guide for laser treatment in these patients.