Objective : To identify the factors affecting the adherence to administration of nucleoside/nucleotide analogues among patients with chronic hepatitis B (CHB), so as to provide insights into improving medication adherence among CHB patients. Methods: CHB patients at ages of 18 to 44 years that underwent treatment in Hangzhou First People's Hospital Affiliated to Zhejiang University School of Medicine from June 2021 to December 2022 were enrolled, and subjects' demographic and clinical characteristics were collected. The medication adherence was evaluated with the Morisky Medication Adherence Scale, and the negative illness perception was evaluated using the simplified Illness Perception Questionnaire, while the social support level was evaluated with the Social Support Scale. In addition, factors affecting the medical adherence were identified using a multivariable logistic regression model among CHB patients. Results: A total of 225 questionnaires were allocated and 210 valid questionnaires were recovered, with an effective recovery rate of 93.33%. The respondents had a mean age of (35.94±8.72) years, and included 119 men (56.67%) and 91 women (43.33%), with a mean total illness perception score of (44.09±12.06) points. Morisky Medication Adherence Scale classified good in 149 cases (70.95%) and poor in 61 cases (29.05%). Multivariable logistic regression analysis identified an educational level of college degree and above (OR=1.676, 95%CI: 1.105-2.910), family monthly per capita income of >5 000 Yuan (OR=2.518, 95%CI: 1.360-5.033), receiving health education pertaining to CHB (OR=3.590, 95%CI: 1.611- 7.932), high or medium level of social support (high: OR=3.202, 95%CI: 1.613-5.870; medium: OR=1.267, 95%CI: 1.085-2.409) as factors improving the medication adherence, and administration of more than 3 types of drugs (OR=0.388, 95%CI: 0.204-0.526) and high illness perception score (OR=0.601, 95%CI: 0.395-0.808) as factors constraining medication adherence among CHB patients. Conclusions The medication adherence are affected by educational level, family monthly per capita income, types of drugs, illness perception score, health education pertaining to CHB and social support level among CHB patients. Individualized intervention strategy is required targeting these influencing factors to improve the medication adherence among CHB patients.