Abstract: In this paper，the complement structure with “得” will be divided into three parts to summarize the errors from the process of Thai students′ acquisition.Second language acquisition theory is used to analyze the causes of the errors.The analysis leads to the conclusion that negative transfer of mother tongue is a main factor leading to errors，as 43．5%errors originate from negative transfer.In this paper，errors are studied from the perspective of the comparison between Thai and Chinese，mainly using the theory of “Hierarchy of Difficulty” combined with statistical analysis of errors according to a questionnaire.Thai students difficulties in the acquisition process of the complement structure with “得” is summarized.The findings will speed up acquisition of Thai students to the complement structure with “de(得)” when applied to teaching of Chinese as a foreign language.

Key words: the complement structure with “de(得)”, acquisition, error analysis, negative transfer, teaching of Chinese as a foreign language, Thai student