The development level of agricultural mechanization is an important index to reflect the extent of agricultural mechanization, and also is the foundation to analyze and measure the grade of agricultural mechanization. The evaluating methods were researched for the development level of agricultural mechanization from the 2 aspects of agricultural mechanization operation and farming machines in place of peasants. According to the concept of agricultural mechanization, the basic characteristics of the agricultural mechanization development were scientifically revealed in different stages, which had the certain theoretical and practical significance. Currently the adopted agricultural mechanization operation level was obtained based on the weighted average method of agricultural mechanization degree of "farming", "planting" and "harvesting" in agricultural production process. Agricultural mechanization level was attained by the revision of agricultural mechanization operation level, which was adding the proportion of agricultural labors in total social workers in the evaluation system; agricultural mechanization index indicated the proportion of agricultural mechanization operation cost in total operation costs including mechanized, animal and manual operation costs. Through the comparative analysis among agricultural mechanization operation level, agricultural mechanization level and agricultural mechanization index, the results showed that agricultural mechanization operation level was suitable to evaluate agricultural mechanization operation degree, while could not truly assess the development of agricultural mechanization, because it only considered the mechanization level of the "farming", "planting" and "harvesting" links in agricultural production process, and did not reflect the effect of farming machines in place of farmers. Nevertheless, agricultural mechanization level and agricultural mechanization index could more accurately reflect the real situation of agricultural mechanization development, because they synthetically took account of the agricultural labor decrease and farming machine operation. Although the 2 calculation methods were different, both of the results were consistent to support each other. Therefore, they could more accurately reflect the real development of agricultural mechanization. Relatively speaking, the maneuverability of agricultural mechanization level was stronger than agricultural mechanization index, because it was obtained from the modification of current agricultural mechanization operation level. In a word, the corresponding evaluation index should be chosen according to the needs and the actual situation in the evaluation process of agricultural mechanization development, but each index should be paid attention to its merits and demerits in the concrete operating practice.