<p>Choosing the right types and amounts of steel fibers and concrete mixtures is important for steel fiber reinforced concretes (SFRC) because they improve the flexural and compressive strength, making the concrete last longer. The variation in input factors, like the compositions of concrete mixes and steel fibers used, affects the unpredictable value of flexural strength. So, the study uses a set of experimental data to explore how steel fibers and different concrete mix compositions influence the flexural strength of SFRC. This study builds a prediction model for the flexural characteristics of SFRC using a database of 147 experimental results obtained from seventeen research groups. A Random Forest model creates an efficient prediction model and discovers key input features affecting flexural strength. The predictive flexural strength model is used along with Latin hypercube sampling (LHS) and a uniform probability distribution of input variables to create a large dataset. Then, the study used Sobol’s global sensitivity analysis method to investigate how different input factors affect the flexural strength of SFRC. The Sobol Index establishes and discusses the order in which input factors influence flexural strength. It is important information for selecting the optimal compositions of steel fiber-reinforced concrete.</p>