The purposes of this research were 1) to study the level of workplace happiness in express international shipping service provider and 2) to study the factors affecting workplace happiness in express international shipping service provider. The sample was 385 employees in express international shipping service provider in Bangkok. Convenient sampling method was used to collect data. The questionnaire was used as research instrument. Statistics used for data analysis included percentages, mean, and standard deviation. Multiple Linear Regression Analysis was used for hypothesis testing. The research findings were: 1) The workplace happiness in express international service provider was at high level. 2) Employment condition, communication, working relationship, job characteristics, and organizational culture could affect workplace happiness in express international service provider at statistical significance level of .01. Compensation could affect workplace happiness at statistical significance level of .05. All independent variables could explain the variation in workplace happiness in express international service provider at 72.1