This study uses 2SLS regression model to examine the relationship between the number of banking relationships and firm profitability in Vietnam. A sample of 81 Vietnamese listed firms includes non-financial firms, 85% of which belong to Information Technology, Industry, Oil and Gas, Pharmaceutical and Medical, Consumer Services. In the sample, 22.2% of the firms have a single bank relationship, 77.8% of them have no more than six relationships. The study constructs two different proxies (ROE and ROA) for firms’ profitability and find that return on equity and return on assets increase as the number of bank relationships rises. The result also shows that firm size and firm age are associated with firm profitability.