<p>This project examined the acquisition of third person accusative clitics in Spanish by Chinese-speaking learners. Specifically, it focused on the role of cross-linguistic influence and patterns of language exposure and use in the acquisition of the syntactic and semantic properties constraining the production and intuition of overt and null clitics in Spanish. An elicited production task and an acceptability judgment task were performed on a total of 83 participants divided into four groups. A group of Chinese immigrants in Spain (n = 24), a group of classroom learners in China with study abroad experience (n = 23), and a group of learners without study abroad experience (n = 19) were compared to a group of native speakers of Spanish (n=17). The results showed that, while all the experimental groups showed knowledge of accusative clitics, their knowledge regarding the distribution of overt and null clitics was generally not related to definiteness or syntactic island. However, some participants with higher proficiency or more use of Spanish showed some sensitivity to the syntactic property of null clitics but not definiteness. Proficiency in Spanish had different effects on the immigrants and the classroom learners. Use of Spanish also played different roles between the pure classroom learners and the other two groups with naturalistic exposure. Finally, the results also showed that, while the three groups all showed influence from Chinese, the Spanish and Chinese grammars of the immigrants showed more similarity, compared to the two groups of classroom learners. Based on a proposed path of acquisition, the results were discussed in line with second language acquisition theorizing on feature accessibility and reassembly. Some implications on classroom instruction are also discussed. </p>