The localization of brain hematoma by using functional near-infrared Spectroscopy has always been a research hotspot in the field of nondestructive optical diagnosis. To achieve open and all-around accurate detection, this paper proposes a new method based on functional near-infrared spectroscopy, the Array scanning sensitivity method. Namely to establish an omni-directional array detector, unilateral array scanning tests to get the fluence rate of different probe locations. By calculating the detection sensitivity, we can get a full range of detection information. Firstly, establish the monolayer finite element model, set optical parameters, light source, detection position and boundary conditions. The simulation results are compared with Monte Carlo to verify the accuracy of the conditions. Secondly, build a brain model with hematoma based on the structure of the brain, the light source selects near-infrared light with a wavelength of 850 nm, the optical parameters of biological tissue at this wavelength are set, simulate the propagation of photons in normal brain tissue and brain tissue with hematoma, and multiple sets of luminous flux data are detected at different locations. After processing the data, it is found that the finite element simulation software can reflect the significant influence of hematoma on the transmission of light in images and data. To study the relationship between luminous flux and the location of the hematoma, the azimuth, horizontal position and depth of the hematoma were changed respectively. Multiple sets of luminous flux data were also detected, the relationship between sensitivity and hematoma location was established for analysis. The results show that the azimuth and horizontal position of the hematoma can be accurately detected by the array scanning sensitivity method, and the detection effect is the best when the hematoma is located between the source and the detection distance. The depth only affects the overall luminous flux, and the deeper the position, the smaller the sensitivity. It is concluded that the array scanning sensitivity method can be used to quickly and accurately locate hematoma in a certain depths of brain tissue, which provides a new way of thinking and an effective reference for detecting tumors and optical imaging in tissue by near-infrared spectroscopy.