The first stag beetle found in Cretaceous Myanmar amber, Electraesalopsis beuteli Bai, Zhang & Qiu gen. & sp. nov., is described and illustrated on the basis of one well-preserved specimen. This specimen provides more detailed morphological characters compared with compression fossils, e.g. the highly setose antennae and the punctured elytra. However, the systematic position of the new genus is still questionable and we provisionally place it as Lucanidae incertae sedis. In addition, the discovery of Electraesalopsis Bai, Zhang & Qiu gen. nov. also indicates that there is very high biodiversity in Burmese amber. The new discoveries in future studies on Burmese amber will provide more information and improve our knowledge of biogeography and early evolution of the Lucanidae.