Energy levels of the double Λ hypernucleus, BeΛΛ11 are calculated within the framework of a ααnΛΛ five-body model. Interactions between constituent particles are determined so as to reproduce reasonably the observed low-energy properties of the αα, ααn nuclei and the existing data for Λ-binding energies of the αΛ, ααΛ, αnΛ, and ααnΛ systems. An effective ΛΛ interaction is constructed so as to reproduce, within the αΛΛ three-body model, the BΛΛ of HeΛΛ6, which was extracted from the emulsion experiment, the NAGARA event. With no adjustable parameters for the ααnΛΛ system, BΛΛ of the ground and bound excited states of BeΛΛ11 are calculated with the Gaussian expansion method. The Hida event, recently observed at KEK-E373 experiment, is interpreted as an observation of the ground state of the BeΛΛ11.
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