This document is a thesis by Nguyen Thi Hong Thuong submitted for a Master of Arts in Development Economics, focusing on the determinants of non-performing loans in the Vietnamese banking system. The study examines both macroeconomic and bank-specific factors affecting non-performing loans from 2006 to 2016, using data analyzed by the system generalized method of moments. It highlights the importance of credit risk on banking health and economic activities, and discusses the negative relationship between GDP growth and non-performing loans alongside the implications of rising interest rates.