A new isoscalar ππ resonance AX(1565) has been observed at a mass of 1565±10 MeV/c2 and a width of 170±20 MeV/c2. The resonance is produced in pp annihilation at rest into π+π-π0 from P states of antiprotonic hydrogen atoms formed b y stopping antiprotons in hydrogen gas at normal temperature and pressure. Annihilation from P states is identified by coincident observations of the LX-ray series emitted in the cascade of pp atoms. The resonance is seen as striking peak in the π+π- invariant mass spectrum. The phase of the π+π- D wave shows a resonance-like behaviour. Hence we assign the quantum numbers IG(JPC) = 0+(2++) to the resonance. © 1989.