The photodissociation dynamics of CH₂Br₂ was investigated near 234 and 267 nm. A two dimensional photofragment ion-velocity imaging technique coupled with a (2＋1) resonance-enhanced multiphoton (REMPI) ionization scheme was utilized to obtain the angular and translational energy distributions of the nascent Br(²P_3/2) and Br^*(²P_1/2) atoms. The translational energy distributions of Br and Br* were found to consist of two components which should come from the radical channel and sec-ondary dissociation process, respectively. By analyzing the angular distributions, the fractions of the direct and non-adiabatic dissociation in the Br and Br^* channels were obtained. It was suggested that Br^* come from the direct dissociation of B₁ state mostly, while Br atom be pro-duced by non-adiabatic transition between the B₁ and A₁ states. Consequently, the phenomena of the higher internal energy distribution of Br channel than that of Br^* forma-tion channel and the broader translational energy distribution of the former can be explained well.

Key words: dibromoalkane, photodissociation dynamics, ion-velocity imaging