The purposes of this research were to study 1) the problems of participatory ecotourism management 2) the assessment of participatory ecotourism management achievement of the management organization, community members, entrepreneurs and tourists 3) the factors affecting the participatory ecotourism management achievement and 4) the model of participatory ecotourism management achievement. The population and sample included community leaders, community committees, entrepreneurs and local people in total of 337 persons. Data were collected using1) the self-assessment form developed by the researcher2) observation and 3) interview. The quantitative data were analyzed in frequency, percentage, mean, deviation, correlation coefficient. The analysis of influent factors, structural equation modeling and causal model were done.
The findings revealed as follows:
1) The problem on the participatory ecotourism management in Koh Samed Sub-district was at a medium level. It was found out that the highest mean score was found in the management organization, the entrepreneur and the tourist while the community member had the lowest mean score.
2) The study on the achievement of the participatory ecotourism management showed that on average the assessment result was a failure, but the mean score showed that the achievement result was at a ready- to- pass criteria.
3) The four factors influenced the achievement of the ecotourism management passed the assessment. The natural conservation and culture had the highest mean score and the management system had the lowest mean score.
4) The pattern of participatory ecotourism management achievement was composed of four factors: management system, the entrepreneur, tourist, and community. The entrepreneur highest affected the achievement, followed by the tourist. And the organization management system directly and indirectly influenced the achievement.
Keywords : Achievement, Management, Ecotourism