Abstract: In a simple aparatus,a method of combing laser ablation,time of flight mass spectrometer and molecular flow has been used to study the reaction of Ni+ with C6~C9 nalkanes in the gas-phase. All the reactions could be explained by the following mechanism: (1) Insertion of Ni+ into C-C or C-H bond ; (2) β-H shift onto Ni+ from one or two of alkyl groups to produce "alkene-like"intermediate; (3) The dissociation of intermediate to produce product ion and neutral molecular.