The results of this study were as follows :
Hypothesis 1 : the difference ages of employees had no difference work motivation which not matched the hypothesis.
Hypothesis 2 : the difference monthly income of employees had no difference work motivation which not matched the hypothesis.
Hypothesis 3 : the difference group of service department of employees had difference work motivation as statistically significant at 0.05 level which matched the hypothesis.
Hypothesis 4 : the difference marital status of employees had no difference work motivation which not matched the hypothesis.
Hypothesis 5 : the difference working experience of employees had no difference work motivation which not matched the hypothesis.
In conclusion, the employees of Soonlee Mahachai Co., Ltd., (Public). who have the different age, monthly income, marital status, and working experience had no difference work motivation which not matched the hypothesis except only the service department of employees had difference work motivation as statistically significant at 0.05 level which matched the hypothesis.