The Ordovician carbonate reservoirs in the Ma5 section of eastern Ordos Basin exhibit complex lithologies, diverse reservoir space type, low porosity and permeability, and intricate pore-permeability relationships. Conventional logging methods cannot accurately determine the fluid properties of the reservoir. At present, there are many methods for identifying the fluid properties of carbonate reservoirs, and constructing fluid identification factor through acoustic parameters is an important means of reservoir fluid identification. This article analyzes and applies the formation characteristics of tight carbonate rocks and the methods proposed by previous researchers. Combined with the acoustic parameters of the elastic properties of reservoir rocks obtained from array acoustic logging data, two sensitive fluid identification factors are selected as the characteristic parameters for fluid identification. The high-sensitivity fluid identification factor is a classification and summary of commonly used fluid factors in seismic data fluid identification. It combines high sensitive parameters into a function form of wave impedance dimension to the power of two, highlighting the resolution ability of fluid identification factors; Based on experimental data, the P-wave and S-wave velocities with small changes in gas saturation are converted into apparent porosity of P-wave and S-wave, and a new acoustic velocity drop factor is created. The trend of change has a good positive correlation with water saturation; Based on well logging data, a fluid identification chart was established for the intersection of high sensitivity fluid identification factors, velocity drop factors, and porosity, forming a method for identifying fluid properties in tight carbonate reservoirs. After verification by gas testing data, the accuracy of fluid identification in tight carbonate reservoirs was improved.