  The prospected sensitivity in $\alpha_\mathrm{S}$ determination using an
event shape observable, ratio of energy correlators at future electron-positron
collider is presented. The study focuses on the collinear region which has
suffered from large theoretical and hadronization uncertainty in the past. The
ratio effectively reduces the impacts of the uncertainties. With the amount of
data that future electron-positron collider could produce in 1 minute (40
$\text{pb}^{-1}$) and 0.5 hour (1 $\text{fb}^{-1}$), a 1% and 0.2% precision of
$\alpha_\mathrm{S}$ could be reached.
