Kinetics of the reactions of isocyanates, isothiocyanates, carbodiimides, carbon disulfide, and carbon dioxide with carbanions or enamines (reference nucleophiles) have been measured photometrically in acetonitrile or DMSO solution at 20 °C. The resulting second-order rate constants and the previously published reactivity parameters N and sN of the reference nucleophiles were substituted into the correlation log k2(20 °C) = sN(N + E) to determine the electrophilicity parameters of the heteroallenes: TsNCO (E = -7.69) ≫ PhNCO (E = -15.38) > CS2 (E = -17.70) ≈ PhNCS (E = -18.15) > PhNCNPh (E = -20.14) ≫ CyNCNCy (E ≈ -30). An approximate value could be derived for CO2 (-16 < E < - 11). Quantum chemical calculations were performed at the IEFPCM(DMSO)/B3LYP-D3/6-311+G(d,p) level of theory and compared with experimental Gibbs activation energies. The distortion-interaction model was used to rationalize the different reactivities of O- and S-substituted heteroallenes. Eventually it is demonstrated that the electrophilicity parameters determined in this work can be used as ordering principle for literature-known reactions of heteroallenes.