The Ni-Al2O3 catalyst was prepared by the mechanochemical method in combination with a planetary ball-milling machine. Effect of milling time on the crystal structure, the reduction characteristics and the catalytic performance of Ni-Al2O3 catalyst for hydrogenation of 1,4-butynediol to produce 1,4-butenediol were investigated. The catalysts were characterized by PSD, EDX, XRD, H2-TPR, BET, TEM, and NH3-TPD methods. Results showed that the MCt2.5 catalyst treated at a ball milling time of 2.5 h could form a smallest particle size of 191.0 nm. The evaluation experiments revealed that the activity of the prepared catalyst increased at ifrst and then reached a constant value with the extension of ball-milling time. The BYD conversion, BED selectivity and yield on the MCt2.5 catalyst reached 35.63％, 33.48％and 32.46％, respectively, which were higher than those obtained by other samples. The excellent performance of MCt2.5 sample is mainly related to the following three reasons from characterization results. Firstly, it has a smallest particle size of 191.0 nm;and then, the surface acidity (in terms of strong acids) of the catalyst was weaker than other catalysts;and eventually, the loading amount (23.84％) of the active component Ni exceeded the theoretical value (20％).