This study aims to: (1) determine the factors affecting credit quality at Vietnam Joint Stock Commercial Bank; (2) analyze the influence of these factors on credit quality at banks. To achieve the above goal, the author used a combination of qualitative and quantitative research methods through SPSS 23.0 software. The research results show that (i) 07 factors affecting credit quality are arranged in descending order of impact, namely: (1) Qualifications of credit officer, (2) Credit policy, (3) Management capacity, (4) Banking technology level, (5) Credit process, (6) Work organizational, and (7) Capital size of the bank; (ii) on that basis, the author proposes some solutions to improve credit quality at Vietnam Joint Stock Commercial Bank.