The current paper performed word association tests on 10 native Mandarin Chinese speakers and 30 English-speaking Mandarin Chinese learners. The aim of the experimental study was to understand the way lexical association is achieved in L1 and L2 learners of Mandarin Chinese. Several major findings followed from our experiment. First, predominantly syntagmatic responses were recorded in the word association patterns of L1 speakers, followed by paradigmatic responses and non-semantic responses. Second, L2 speakers whose native language is English resembled the pattern of responses by L1 speakers, with the main difference being that a higher percentage of non-semantic responses were recorded for L2 speakers with lower lexical proficiency. Third, the word association pattern of L2 speakers tended towards that of L1 speakers as language proficiency progressed. It is further found that the extent to which lexical proficiency progresses is a function of the duration of residence in the country of target language.