Thailand is one of the world suppliers of agricultural produce. Approximately 21 million ha or 40.9% of the total area is used for agricultural production. About 49.8% of the agricultural land is used for growing rice, 21.5% for field crops, 21.2% for fruit or horticultural crops and 7.5% for others. Agriculture is an important sector and the largest source of employment of rural population of the country. About 46.6% of the total population is engaged in this sector. Mechanization plays a vital role in the present Thai agricultural production system. Labor shortage and necessity to reduce production cost have become pressing. This paper presents an overview of agricultural mechanization in Thailand, the status of agricultural machinery industry, the distribution/supply chain of agricultural machinery, agricultural mechanization policies, challenges and constraints of a sustainable agricultural machinery sector and the potential role of the agricultural mechanization associations in Thailand.