The new fishbone technology is a new technology for increasing production, which has the characteristics of no fracturing, low cost, simple construction, full diameter of tools and so on. The purpose of this technology is to connect the wellbore with the gas reservoir through nearly 100 fishbone branches to increase production, and it has a broad prospect in low permeability tight gas reservoirs. In order to reveal the influence of branch completion parameters on productivity, the unstable productivity response solutions of fractured horizontal wells and fishbone wells are established according to percolation theory and continuous point source technology, and the productivity differences between fractured horizontal wells and fishbone wells are compared. The influence of completion parameters on productivity logging is discussed. The results show that under the same reservoir parameters and production system, the production of fishbone well is lower than that of fracturing horizontal well, and the flow rate of each fracture is higher than that of fishbone branch at the same time, because the interference pressure drop of fishbone branch is higher than that of fracturing horizontal well. The output of fishbone well increases with the increase of branch angle, mainly because the percolation interference pressure drop decreases with the increase of branch angle. With the increase of permeability, the cumulative gas production increases, and there are optimal parameters under the condition of specific permeability; the branch spacing increases, the productivity increases, and the influence of branch interference weakens, forming the adaptive range and optimization scheme of fishbone wells in tight gas reservoirs. It has important guiding significance for the efficient development of tight gas reservoir.