Chronic hepatitis B (CHB) patients may be unsatisfied to entecavir (ETV) therapy due to the inconvenience in drug taking, i.e., fasting for more than 2 hours and/or dose adjustment according to estimated glomerular filtration rate (eGFR). However, tenofovir alafenamide (TAF) has been approved to be highly effective and safe in patients with CHB, and is convenient in drug taking, i.e., once daily regardless food taking and renal function.Therefore,TAF can be a good option in CHB patients who are unsatisfied to ETV therapy. The aim of this prospective cohort study is to assess the improvement on satisfaction (including drug adherence) of TAF switch therapy in CHB patients who are unsatisfied to ETV therapy. In addition, with expected adherence improvement in TAF switch therapy, the efficacy of TAF switch therapy may be improved, and the efficacy benefits can be evaluated by the changes of some novel biomarkers, such as HBV core-related antigen (HBcrAg). The investigators therefore aim to conduct a prospective cohort study of TAF switch therapy for CHB patients who are unsatisfied to ETV therapy.