Objective To analyze the impact of subjective cognitive function on the improvement of social function in patients with first-episode depression during the acute phase （within 8 weeks）. Methods This study was prospective and observational. From March 2016 to February 2017， 260 first-episode depression patients who visited the outpatient department of Beijing Anding Hospital were selected as the research subject. The severity of depressive symptoms， subjective cognitive function， and social function impairment were evaluated using the 17-item Hamilton Depression Rating Scale （HAMD-17）， Perceived Deficits Questionnaire for Depression （PDQ-D）， and Sheehan Disability Scale （SDS） at baseline， on the fourth weekend， and eighth weekend， respectively. Spearman correlation was used to explore the correlation between the scores of PDQ-D， HAMD-17 and SDS. The repeated measurement mixed effect model of time-dependent variables was used to analyze the differences in subjective cognitive function of patients and the impact of subjective cognitive function on social function improvement. Results At baseline， the PDQ-D， HAMD-17， and SDS scores of first-episode depression patients were （32.85±16.48）， （23.12±4.66）， and （17.32±7.07）， respectively. On the fourth weekend， the scores were （25.75±0.96）， （13.86±0.39）， and （12.36±0.50）， respectively. On the eighth weekend， the scores were （21.69±0.97）， （10.33±0.38）， and （9.37±0.47）， respectively. Correlation analysis showed that the baseline PDQ-D score of patients was positively correlated with HAMD-17 and SDS scores， and the difference was statistically significant （r=0.30， 0.49； P＜ 0.001）. On the eighth weekend， the PDQ-D score of patients had a statistically significant impact on SDS score （P ＜ 0.001）， while education level， duration of the disease， and type of antidepressants had no significant impact on the social function impairment （P＞ 0.05）. Conclusions The changes in subjective cognitive function of first-episode depression patients during the acute phase can affect social function.