When learners with multilingual backgrounds learn Chinese as a third language，they often regard both the second language and the third language as foreign languages，and do not realize that the vocabulary strategies of learning the two languages are different，and teachers may also ignore the differences between the two. Differences，habitually teach second language vocabulary learning strategies to students，which is detrimental to learners’ learning and teachers’ teaching. Therefore，learners and teachers should pay attention to the positive impact of second language vocabulary learning strategies，and apply them in the learning and teaching of Chinese as a third language vocabulary in a targeted manner. Through a questionnaire survey on learners of Chinese as a third language in Mozambique，this paper puts forward specific suggestions on vocabulary learning strategies for Chinese trilinguals，so as to promote Chinese as a third language learners to better use vocabulary learning strategies，which will help Chinese teachers. Vocabulary teaching provides more guided advice.