Rates of chemical absorption of $CO_2$ in water-in-oil (w/o) emulsion were measured in a flat-stirred vessel at $25^{circ}C$. The w/o emulsion was composed of aqueous monoethanolamine (MEA) droplets as a dispersed phase and non-Newtonian viscoelastic benzene solutions of polybutene (PB) and polyisobutylene (PIB) as a continuous phase. The liquid-side-mass transfer coefficient ($k_L$) was obtained from the dimensionless empirical equation containing Deborah number expressed as the properties of pseudoplasticity of the non-Newtonian liquid. $k_L$ was used to estimate the enhancement factor due to chemical reaction between $CO_2$ and MEA in the aqueous phase. PIB with elastic property of non-Newtonian liquid made the rate of chemical absorption of $CO_2$ accelerate compared with Newtonian liquid.