Thailand is currently a developing country, its fundamental economic system is still
predominantly driven by small and medium business units. Thus, giving support and
encouragement to small and medium-sized enterprises (SMEs) is the most important policy
in strengthening the Thai economy, in order to be able to grow and develop like others
countries such as the United Kingdom, Germany, Finland, Australia, Japan and Malaysia.
The aims of this research are to study factors which are affecting the happiness of
employees at work in SMEs and to measure the level of happiness at work. A total of 300
employees were investigated by structured questionnaires. The conceptual framework was
developed by five factors of happiness in the workplace which were 1) job inspiration 2)
organization’s shared value 3) relationship 4) quality of work life; and 5) leadership. The
results shown that the level of happiness of SMEs employees in Chiang Mai was at the high
level and the level of opinion towards the five factors affecting happiness at work was also at
the high level. Relationship, quality of work life and leadership were three factors that led to
happiness at work and able to predict happiness at work. The prediction ability was at 59.4%
(R Square=0.594)