By means of ion‐beam‐analysis techniques, the trapping of deuterium implanted into nickel preimplanted with helium was investigated in the temperature range 100–500 K. Following room‐temperature helium implantations and deuterium implantations at ∼100 K, linear‐ramp annealing (1–2 K/min) was carried out, while the deuterium concentration within the near‐surface region (0–0.5 &mgr;m) was monitored by use of the nuclear reaction D(3He,&agr;)1H. The release curves were analyzed by solving a diffusion equation with the appropriate trapping terms. In addition to trapping by lattice defects, stronger helium‐associated traps were found with a binding enthalpy of 0.55±0.05 eV relative to a solution site. We propose that the responsible entities are small helium bubbles observed in the implanted material by transmission electron microscopy.