In article, digitization process of gravimetric data is described. During the process different and uneven coverage of historical data was faced. Consequently, input data obtained were uncomplete, in particular, in the Baltic Sea. Therefore it was necessary to apply altimetric measurements by satellite ERS-1, which were converted into gravimetric data. After the obtaining and analysis of before-mentioned input data in the next stage of work, national gravimetric geoid in several combinations was calculated by use of special software GRAVSOFT. Comparison of several solutions for the geoid model, for which different amount of gravimetric data was applied, allows to come to conclusion that inclusion of altimetric data into modelling of geoid gives improvement of accuracy for 1.3 cm to us.