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In this manuscript, we have explored the reaction mechanism, kinetics and global warming potentials of Z- and E-isomers of CF3CH=CHC2F5 molecule initiated by OH radical to understand its impact on the atmospheric environment. Energy profile diagram for OH-initiated reaction pathways for these two isomers are constructed from the data obtained at M06-2X meta hybrid density functional theory along with aug-cc-pVTZ basis set. The observed potential energy and enthalpy and Gibb's free energy of the reactions suggest that OH-addition to Z- and E-isomers is more feasible than the hydrogen abstraction reactions. The rate coefficients of each reaction channel are evaluated by using conventional transition state theory within the temperature range of 200-350 K. We found that the overall rate coefficient for Z-isomers decreases with the increasing temperature, whereas this value increases for E-isomer with the increasing temperature. The overall rate coefficients for both isomers (Z and E) are fitted to modified Arrhenius three parameters and expressed as k(overall(Z)) = 9.06 x 10(-21) T-2.20 exp (1054.89 +/- 0.93/T) and k(overall(E)) = 1.09 x 10(-21) T-2.77 exp (394.40 +/- 1.52/T) cm(3) molecule(-1) s(-1) respectively. The calculated rate coefficients and branching ratios for each reaction channels indicate that OH radical addition to unsaturated carbons of Z/E- CF3CH=CHC2F5 molecules are more dominate to the overall reaction than H-abstraction reactions. Finally, we have estimated atmospheric lifetimes and GWPs of Z- and E-isomers of CF3CH=CHC2F5 molecule. (C) 2019 Elsevier Ltd and IIR. All rights reserved.