The problem. The purpose of this study is to investigate positive and negative cross-linguistic transfer on EFL learners' phraseological competence in collocations and its relationship to learners' linguistic proficiency. Method. A quantitative study was conducted. Two instruments, multiple choice test and grammaticality judgment test, were developed to examine the extent that cross-linguistic transfer manifests itself in participants' phraseology. A total of 265 EFL college students served as subjects for the study, and were divided into three proficiency levels: intermediate, high-intermediate and advanced. Besides cross-linguistic transfer, L1-L2 congruency effect and instrument type effect were also investigated to determine the potential factors that affect learners' phraseological competence in collocations. Moreover, the relationships of participants' linguistic proficiency with their collocational competence, cross-linguistic transfer, and L1-L2 congruency effect were also examined. The data were analyzed using the SPSS statistical package, which included descriptive statistics, t-tests, one-/two-way ANOVA, Scheffe post hoc multiple comparisons, and Pearson production-moment correlations. Results. The results revealed that learners' phraseological competence, as defined by accuracy for collocations with the delexicalized verbs "do," "have," "get," "make" and "take," significantly correlated with their linguistic proficiency. Learners' phraseological competence was also significantly impacted by the effect of L1-L2 congruency, and the effect significantly correlated with learners' linguistic proficiency. However, there was no interaction between the accuracy of collocations by the L1-L2 congruency and learners' proficiency levels. That is, the advanced group scored higher on both congruent and non-congruent collocations in comparison with the other two groups, and vice versa. The findings of the study also showed significant differences in language transfer between the three levels, and language transfer significantly correlated with learners' L2 proficiency. With regard to the effect of instrument type, it was found that the advanced learners, who had significantly higher scores on the multiple choice test, also consistently scored significantly higher on the grammaticality judgment test as compared to the other two groups, and vice versa. Finally, in addition to negative cross-linguistic transfer, the effect of intra-lingual confusion also accounted for learners' errors, in that misuse of delexicalized verbs was strongly influenced by their lexical meanings in English. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]