Purpose: To investigate the distribution and influencing factors of pre-operative conjunctival flora from patients undergoing penetrating ocular surgeries in northeast of China.Methods: An observational and cross-sectional study design was used. In 305 eyes of 305 patients without infective eye diseases who underwent ocular surgeries in the First Affiliated Hospital of Harbin Medical University between May 2018 and May 2019, conjunctival sac scrapings were collected on the day before surgery.Results: The mean age of participants was 60.73 ± 14.23 years, with the majority being female, married and unemployed with at least primary school education. The positive culture rate was 48.20% (147/305 eyes), and a total of 191 bacterial strains were isolated, 22.45% (33/147) positive samples had two or more strains isolated. The most commonly isolated bacteria was Staphylococcus epidermidis (64.92%), surpassing Staphylococcus aureus (5.76%). The culture positive rate of young (18-40 years) group was different between the females(26.67%) and the males(69.23%)(P = 0.024), but in middle aged group and the elderly group, the rates between the sexes were similar with increased trend. Patients visited in summer or autumn presented a higher positive rate than other seasons. The hypertensive women had a higher rate than hypertensive men(58.14% vs. 40%, X2 =5.8662,P = 0.0154). Conclusions: In northeast of China, coagulase-negative Staphylococcus were the most common pre-operative conjunctival bacteria. The hypertensive female patients, elderly patients, or operated patients in summer and autumn should pay more attention to perioperative treatment.Trial registration number:ChiCTR2100044659