Wireline formation testing is an important technique in the exploration and development of oil fields. Not only can real fluid samples be prepared from the formation directly obtained to know exactly whether the oil existed in the formation or not, but it can also show flowing pressure change to determine the production capacity of the formation. So, it is an important measurement method for formation evaluation during the drilling process and supports activities related to the exploration and development of oil fields. A numerical simulation model in this article is researched and established based on the finite volume method considering the influence of sensitive parameters such as reservoir heterogeneity, probe suction area, and mud-filtrate invasion depth during the drilling. The model is capable of designing and evaluating formation fluid sampling operations by calculating hydrocarbon content and flowing pressure. Furthermore, through case application, the performance and effect of the process of wireline formation testing were investigated. The results indicate that this technology can serve as an effective auxiliary tool for fluid sampling operations with the function of optimizing fluid sampling measures. It can improve the accuracy of predicting indicators such as hydrocarbon content and breakthrough time during the sampling process. This study provides important supporting evidence and technical guidance for professionals in geological exploration and oil field development.