The article presents the study results of the influence of the orientation of a vertical crack from hydraulic fracturing treatment on the efficiency of oil reserve recovery, indicating the crack propagation direction. It was found that the increase in initial recoverable reserves is the greater, the longer the crack length is, and if the crack is oriented parallel and perpendicular to the filtration flow down to the permeable zone in the stagnant or deadlock zone, then the perpendicular connecting current lines from the injection well to the recovery well is most effective. The presented results show that HFT significantly changes the conditions for the oil reserve recovery in general in the reservoir area. Therefore, it is relevant to assess the contribution of a single HFT to the oil recovery factor of the reservoir area, as well as its effect on the wells density grid.