Nuclear Power Plant (NPP) of Dabaa region -Egypt is considered as one of the new energy sources (for energy conversion from nuclear to electric type). However, emission of radioactive nuclide must be quantitatively assessed especially in case of nuclear accidents. Therefore, the present study uses the lagrangian flexible particle dispersion model (FLEXPART) version 10.4) to calculate the concentration and total deposition of Cs-137. FLEXPART is driven by the NCEP FNL (Final) Operational Global Analysis and the model simulation is integrated over the period 2008-2018. Possible risk is assessed assuming a hypothetical accident scenario based on probabilistic risk assessment method. Moreover, average wind speed and direction as well as the total surface precipitation are also considered to examine the possible influence of these weather factors on dispersion of the emitted radionuclide, its concentration and total Deposition. The results show that high concentration and total deposition are observed particularly during the summer season. Also, considering different emission scenarios indicate that Egypt is expected to be strongly affected. In conclusion, FLEXPART is considered as a promising tool to explore the possible nuclear hazards under a variety of meteorological conditions. Further, a future study will consider the influence of the horizontal grid spacing and lateral boundary condition using the coupled Weather Research and Forecasting (WRF)-FLEXPART system.