This article attempts to collect a data set of labour unions in global 500 biggest banks and investigate whether labour unions of banks influence the designing of bank loan contracts. We use global syndicate loan market to examine this issue. For simplicity, banks with and without labour unions are referred to as ‘unionized banks’ and ‘nonunionized banks’, respectively. We find that unionized banks tend to loosen their lending standard in the bank loan contract: unionized banks are more likely to charge lower loan spread and favourable nonprice terms compared with nonunionized banks. Hence, our results support that unionized banks tend to lend more loans to reduce the negative effect of labour unions.