The objective of this independent study was to study happiness at work of employees at Akara Mining Company Limited, Phichit Province. The data from this study was collected from 365 employees at Akara Mining Company Limited. The tool to collect the data was a self-administered questionnaires which consisted of questionnaire for general information, questionnaire on happiness at work, questionnaire on the level of potentiality and capacity to work to the fullest level, and questionnaire on happiness at work and work result. The data was analyzed using statistics, namely frequency, percentage, mean, T-test, One-way Anova, Least Significant Difference and Linear Regression. The results of the study showed that most employees were female, 36-40 years old, married, with education below Bachelor’s degree. Their work experience and work period were not more than 5 years. Most of them were general staff. The opinion of the employees towards factors for happiness at work was at the “agree” level, and the employees ranked the 5 factors in the following order: reliability, conviction, organisational culture, and confidence. They ranked work at the “somewhat agree” level. From Linear Regression analysis to establish the relationship between the factors affecting happiness at work and important characteristics that created happiness, it was found that all factors affecting happiness at work were generally related to important characteristics that created happiness, with reliability showed the most prediction capability. The other factors were work result, organisational culture, and confidence, respectively. It was also found that the relationship between 3 important characteristics that created happiness and the level of potentiality and capability to work to the fullest level was positive.