This paper presents the geotechnical assessment and classification of ultrabasic rock masses in the south of Mashhad. Both field and laboratory studies were carried out. The field study involved discontinuity surveying and jointing parameter and also calculation of block size measurements (weighted joint density and block size). Laboratory test were carried out to determine uniaxial compressive strength and point load values.The block size measurement methods and also RMi and GSI classification systems were performed to determine the excavatability in the studied rock masses. Considering to obtained results, using ripper in the excavatability is the best method. According to RMi classification system, the ultrabasic rock masses are described as moderately strong to strong. Also according to the GSI system, these rock masses are described as very blocky.

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