The objective of this study is to examine the vowel duration that follow word initial-plosives in Korean language produced by Chinese learners, to identify its characteristics and propose how to use the following vowel duration for teaching pronunciation of word initial-plosives. To this end, 20 native Korean speakers from Seoul and Gyeonggido Province in their 20s and 20 Chinese speakers from Shandong Province in their 20s participated in the production experiment. They were asked to pronounce nine word initial-plosives in each sentence unit, and the vowel duration was analyzed. According to the result, native Korean speakers produced the longest sound for vowels that followed fortis, while producing shorter sounds for the following vowels of lax and aspirated. Another observation was an inverse relationship between VOT of word-initial plosives and the vowel duration. In comparison, the vowel duration produced by Chinese speakers had no differences among lax, aspirated, and fortis. Also, an inverse relationship was not observed between VOT and the vowel duration. To examine the effect of education, we taught Chinese participants that the vowel duration should vary by the phonation type of word initial-plosives. Afterwards, we asked them to read the same sentences again, and measured the vowel duration. The vowel duration produced by Chinese participants after the instruction remained different from that produced by native Korean speakers. However, compared to pre-instruction test, Chinese participants produced shorter sounds for the following vowels of lax and aspirated consonants. This suggests that the characteristics of the vowel duration by different phonation type can be applied to teaching word initial-plosives in Korean language. Teaching Chinese learners of Korean language to pronounce the vowel duration of fortis longer than the following vowel of lax or aspirated would help them make a distinction between lax and aspirated, and correctly pronounce them. (Korea University)