The presence of the invader eucalyptus gall wasp Leptocybe invasa Fischer & La Salle (Hymenoptera: Eulophidae) is recorded for the first time in Mexico. This forest pest has been detected in northern México City, at an elevation of ≈2,240m, with an average temperature of 17.9°C. It has also been detected in the areas of Nezahualcóyotl and Texcoco, State of México; Cuautla, Morelos; Guadalajara, Jalisco and Ciudad Victoria, Tamaulipas. In these states, L. invasa attacked Eucalyptus camaldulensis Dehnh. About 2.6% of the E. camaldulensis trees reported in México City had infestations in about 27% of the twigs. In addition, 25% of the leaves had galls, with an average of 23.5±4.8 galls per branches of 20cm in length.