Boron-Neutron Capture Therapy (BNCT) is a cancer treatment method that selectively eliminates tumors in the body by utilizing the high capture reactivity of boron and neutrons. In this paper, Imaging of the prompt gamma-ray by the boron-neutron capture reaction was studied. Semiconductor based detectors have good energy resolution but are not suitable for imaging equipment because of their disadvantage that they are very expensive, have a short lifetime due to aging in a high radiation environment, and some detectors have to be used under limited conditions such as cooling. On the other hand, the scintillator based detector has a relatively low energy resolution than the semiconductor detector but has a merit that the price is relatively low and the large area for imaging is relatively easy. Recently reported SrI2 scintillator was reported to have good energy resolution of 2.6-3.5% (@662 keV), which is likely to be advantageous for the detection of gamma rays by boron-neutron capture reaction. The SrI2 scintillator based imaging system was designed and the system was verified and evaluated by Monte Carlo simulation. The prototype model of the imaging system was implemented and images were acquired using a gamma-ray source. It was confirmed that prompt gamma-rays could be generated and imaged by the boron-neutron capture reaction through Monte Carlo simulation using GATE (v7.0). In the condition with scattering material, the scatter was distributed throughout the region of interest of the detector due to the effect of the gamma ray (2223 keV) which generated in the hydrogen-neutron capture reaction, Particularly, annihilation gamma-ray was the main factor. It is possible to image prompt gamma-ray using conventional parallel hole collimator specifications. However, the prompt gamma-ray image showed an asymmetrical pattern centered on the boron region and has low image contrast. Iterative reconstruction method (MLEM) for acquiring a tomography image of gamma-ray was better than an analytical reconstruction method (BP, FBP) and depth of boron region could be confirmed through the acquisition of tomography image. A prototype model of the designed imaging system was implemented in a physical experiment. Tomography images were acquired using F-18 source (511 keV), which emits energy similar to the prompt gamma rays generated by the boron-neutron capture reaction. In the physical experiment using monolithic SrI2 scintillator, we could detect 511 keV gamma-rays with the energy resolution of 3.56%, which is the ability to discriminate between gamma-ray and gamma ray in the actual boron-neutron capture reaction experiment. The energy resolution of the discrete SrI2 scintillator was lower than that of the monolithic scintillator (10.70%@511keV), and the energy resolution was improved (7.32%@511keV) by peak correction. Tomography images of high energy gamma-ray source (511 keV) could obtain by using discrete SrI2 scintillator. In the experiment, the iterative image reconstruction method (MLEM) showed the best image performance. It is possible to imaging of prompt gamma-ray during BNCT using SrI2 scintillator based imaging system.