Objectives/Scope: Mahu reservoir is the largest conglomerate reservoir recently discovered in China. Considering the significant differences in geology, rock mechanics, in-situ stresses, fracturing parameters between different fields, the productivity of horizontal wells is affected by myriad factors. Clarifying the influencing factors of horizontal well productivity in Mahu tight conglomerate reservoirs can not only improve the single well oil production, but also improve the reservoir recovery rate. Methods, Procedures, Process: In the Mahu demonstration area, a variety of pilot tests were carried out, such as single stage 3 clusters with cluster spacing of 20 m, 6 clusters per stage with cluster spacing of 10 m, 6 clusters per stage with cluster spacing 10 m, 2 clusters per stage with cluster spacing of 30 m. To compare the implementation effect of various fracturing tests, and provide a basis for fracturing test, the influencing factors of fractured horizontal well productivity were revealed. Results, Observations, Conclusions: According to the analysis results of productivity control factors of horizontal wells, the thickness of high-quality formation layers, cluster spacing and proppant concentration are the primary influencing factors. Meanwhile, the productivity of horizontal wells is also affected by well spacing, reservoir pressure and oil saturation. An overlarge fracturing scale will prolong the frac fluid flowback and affect oil production rate. The field test of “slippery water plus nanoemulsion” has achieved the expected production effect. Novel/Additive Information: According to the field pilot test of the fracturing horizontal wells in Mahu (high strength proppant, fracturing fluid strength and proppant concentration), the influencing factors of the production of fractured horizontal wells in tight conglomerate can be revealed effectively. The valuable field test data has a great significance for the fracturing design of horizontal wells.