Developing efficient Ni based hydrogenation catalysts to achieve the directional synthesis of 1,4-butanediol from 1,4-butynediol hydrogenation is the keypoint to building a high value extension industrial chain for coal based primary chemicals. Aiming at solving the problems of Raney Ni catalyst widely used at present, such as lacking support, low activity specific surface area, and poor hydrogenation selectivity, a Ni/AC catalyst with well-developed pore structure activated carbon (AC) as support was prepared in this work, and the structure-activity relationship between catalyst structure and performance was discussed by combining characterization methods. The results showed that with the increase of Ni loading, the active nickel species exposed on the activated carbon surface increased at first and decreased later, and the hydrogenation activity also show as volcanic distribution. The 25% Ni/AC catalyst loaded with 25% Ni had the highest selectivity of 1,4-butanediol, reaching 86.2%. At this time, the selectivity of 1,4-butanediol and 2-hydroxytetrahydrofuran, the semi hydrogenation products, were 1.2% and 6.8%, respectively. Due to the highly dispersed active Ni species in this sample, a large amount of active hydrogen is provided, which promotes the hydrogenation reaction. Due to the long distance between Ni active centers and the low density of surface active H on catalysts with low Ni loading, isomerization side reactions are prone to occur to generate 2-hydroxytetrahydrofuran. At high Ni loading, the aggregation of Ni species results in the decrease of hydrogenation activity.