In recent years, significant breakthroughs have been achieved in the exploration and development of the X block. However, previous studies have mainly focused on the Upper Paleozoic, and the understanding of the geological characteristics of the Lower Paleozoic Majiagou Formation in this block is still insufficient. In order to enhance the understanding of this block, this paper comprehensively studied the reservoir characteristics and fracture features of the Majiagou Formation, specifically the Ma5 member, in the study area, combining core observation, thin section analysis, interpretation of logging data, and existing knowledge. The results show that the carbonates in the study area are mainly composed of finely crystalline dolomite, with pore types dominated by intercrystalline dissolution pores, micropores, microfractures, and dissolution holes. The matrix pore storage capacity, pore structure, and reservoir permeability are relatively poor. The fracture width is generally less than 1 mm, with a density ranging from 5 to 20 fractures/m, predominantly occurring at angles of 35–75°. Fracture apertures are generally developed, with the most developed fractures found in the Ma541, Ma542, Ma53, Ma52, Ma514, Ma543, and Ma511 layers, mainly concentrated between 0.001 mm and 10 mm. Fracture density is generally developed, with more developed fractures observed in the Ma514, Ma521, and Ma541 layers, primarily concentrated between 1 and 100 fractures/m, while relatively fewer fractures are observed in other layers. The aforementioned study deepens the understanding of the study area and can provide guidance for the subsequent production increase in this block.