The purpose of this study was to investigate how vocal attack time (VAT) varies when young adults articulate the three vertex vowels in Mandarin Chinese at five linguistically unconstrained pitch levels. Sound pressure and electroglottographic signals were recorded simultaneously from 53 male and 53 female subjects saying sustained /A/, /i/, and /u/ at five equally spaced pitch heights, each being higher than the preceding one. Then analyses of means, variance, and correlation were performed to explore the relationships of VAT/pitch levels and VAT/vowels. Findings were As mean STs (semitone) increase linearly from levels 1 to 5, mean VATs decrease nonlinearly in a big group of subjects but increase nonlinearly in a small group of them. Based on the body-cover model of F0 control, data here lead to the guess that different people incline to use different strategies in increasing pitch height. When males, females, and males plus females are considered as a whole, average STs and VATs tend to be positively correlated among the three vertex vowels.