Nowadays in situ geotechnical tests are used by the geotechnical engineers in a variety of forms. The SPT test, due to the simplicity, low cost, and association with other soil parameters, is using widely in engineering projects. The results of this test are associated with only a point, while the project engineers need information about the whole project area, especially the places with not samples. Therefore, using of geostatistical and interpolation methods to produce maps of soil engineering parameters is very common. In this research, the examined results of SPT in 18 study boreholes within the area of Chehel Baze national park of Mashhad city, according to blows change from 10 to 50, using geostatistical methods and general Kriging tool, the map of SPT changes and the estimation error maps was prepared. According to the results, it seems that geostatistical methods due to the acceptable precision and nature of geotechnical parameters, is a useful tool for predicting the number of SPT for area that tested data is not available.

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