Organocatalytic asymmetric [3 + 2] cycloaddition reaction of 3-(2,2,2-trifluoroethylimino)-1-methylindolin-2-one ylide TFMY with the cinamaldehyde CIA and with the corresponding iminium ion CIM, is studied using molecular electron density theory. This reaction which leads to the formation of certain CF3-containing spiro[pyrrolidin-3,2′-oxindoles] has been explored experimentally by Ma and coworkers. Analysis of the global CDFT indices revealed that CIA as well as CIM show a more negative value of electronic chemical potential in comparison to TFMY. In addition, it was found that by conversion of CIA to the corresponding iminium ion CIM, the global CDFT indices change significantly. In order to study the regioselectivity, the local reactivity indices based on the Parr functions were calculated and the results showed an excellent agreement with the experimental outcomes. The diastereoselectivity of the reaction was investigated by PES analysis and a good agreement was observed with the experimental results. By calculation of the molecular electrostatic potential (MEP) map for transition states, it was found that the electrostatic forces between two fragments can explain the observed diastereoselectivity. The enantioselectivity of the reaction was also investigated with an emphasis on the effect of the chiral organocatalyst (diphenylprolinol silyl ether 5) on the [3 + 2] cycloaddition reaction. The PES analysis showed that the bulky group located on the organocatalyst in the iminium ion CIM determines the direction of the cycloaddition. Indeed, by conversion of CIA to CIM, the reactivity, regioselectivity and enantioselectivity are significantly improved in reaction. The molecular mechanism of the asymmetric reaction was investigated by the IRC and QTAIM analyses and the results suggested a two-stage one-step mechanism for the reaction. Finally, by calculation of the rate as well as equilibrium constants for deprotonation of TFMY precursor, it was found that the CF3 group as an electron-withdrawing one plays an important role in the production of TFMY.