Teacher is the nucleus of the whole educational system and is of the significant impact on children’s learning. This paper investigates challenges of Cambodian teachers in contributing to their nation’s future human and social development. In order to achieve that development, are Cambodian teachers well-trained? To clarify, a questionnaire was distributed to a line of Cambodia’s educational staff from local to central. A section of the questionnaire was extracted for this paper. The results revealed that educational development in Cambodia faces severe challenges due to severe shortage of qualified trained teachers. Up to present, some teachers have not experienced in any pedagogical training. Furthermore, despites few officials who are PhD holders, some are primary school graduates or even not finished primary level. Moreover, in-service training has not yet been systematized and has been provided to teachers not regularly. Thus, feasible in-service training programs for Cambodia’s teachers appear urgent to be structured for their continuous professional development so as for contributing to human and social development.