Résumé : The Λ9Li→π-+9Be*→π-+p+8Li and Λ9B→π-+9C*→π-+p+8B decay modes were investigated. The existence of an isospin- 3 2 state of 9Be, with excitation energy 18.6 ± 0.1 MeV and width Γ ≲ 300 keV has been established. From a reanalysis of European K- Collaboration emulsion data, new values of the binding energies of 9ΛLi and 9ΛB hypernuclei were found as 8.50 ± 0.12 MeV and 8.29 ± 0.18 MeV, respectively. © 1985.