A method for determining geometric characteristics of a hydraulic fracture comprising: - performing a baseline seismic survey for a geological formation, the survey including excitation of first seismic signals by at least one seismic source and registration of first reflected and refracted seismic signals by at least one seismic receiver, - performing hydraulic fracturing, - performing seismic surveys after fracturing whilst the fracture is maintained open and pressurized, the surveys including excitation of second seismic signals by at least one seismic source and registration of second reflected and refracted seismic signals by at least one seismic receiver, and determining geometric characteristics of the fracture by comparing the first and the second reflected and refracted seismic signals, characterized by that before fracturing - a velocity model is created by combining results of the baseline seismic survey and additional geoscientific information, - seismic properties of the geologic formation are evaluated, - at least one strong flat lithological reflector disposed below a planned fracture is identified using the velocity model, - a numerical model of elastic wave propagation in the geologic formation with a fracture with given properties is created and the positions of the seismic sources and receivers and their properties are optimized on the basis of the numerical model taking into account the depth of the identified reflector, geometry and position of the planned fracture, and - a series of numerical calculations is performed modelling the propagation of the seismic waves in case of the presence of the hydraulic fracture with different combinations of geometrical characteristics in order to solve an inverse problem and determine the fracture geometry that in the best way corresponds to the recorded seismic response. - performing a baseline seismic survey for a geological formation, the survey including excitation of first seismic signals by at least one seismic source and registration of first reflected and refracted seismic signals by at least one seismic receiver, - performing hydraulic fracturing, - performing seismic surveys after fracturing whilst the fracture is maintained open and pressurized, the surveys including excitation of second seismic signals by at least one seismic source and registration of second reflected and refracted seismic signals by at least one seismic receiver, and determining geometric characteristics of the fracture by comparing the first and the second reflected and refracted seismic signals, characterized by that before fracturing - a velocity model is created by combining results of the baseline seismic survey and additional geoscientific information, - seismic properties of the geologic formation are evaluated, - at least one strong flat lithological reflector disposed below a planned fracture is identified using the velocity model, - a numerical model of elastic wave propagation in the geologic formation with a fracture with given properties is created and the positions of the seismic sources and receivers and their properties are optimized on the basis of the numerical model taking into account the depth of the identified reflector, geometry and position of the planned fracture, and - a series of numerical calculations is performed modelling the propagation of the seismic waves in case of the presence of the hydraulic fracture with different combinations of geometrical characteristics in order to solve an inverse problem and determine the fracture geometry that in the best way corresponds to the recorded seismic response.