In the second half of the 20 century, echosonography has been used in many medical specialities. In 1992 and 1993 highfrequencies echosonography was used in the examination of irritant and allergic skin lesions in order to examine the effects of different therapeutical agents on the skin lesions [1-4]. Hoffmann used highfrequencies echosonography in the examination of healing of skin lesions [3]. By their incidence skin tumours are the largest group of newly discovered tumours, and their usual location is on the face [5-7]. By clinical examination it is not possible to precisely determine the depth of tumour border; therefore, the radically performed surgical excision is the only correct surgical treatment. The aim of this study was to estimate the results of preoperatively performed high frequencies echosonography in order to reduce the number of incorrectly performed surgical excisions of skin tumours. The group was composed of 40 patients with 45 tumours, who first underwent echosonographic diagnostic procedure (20 MHz, Hadsund electronic, Hadsund Technology, Denmark) and then surgical excision; patients in control group (45 patients with 45 tumours) were only subjected to surgical excision. Excised tumours were then pathohistologically analyzed, and measurements of tumour depth progression were performed. Margins of pathohistological specimen were controlled for the presence of tumour cells. Results of measurements of tumour depth obtained by echosonography and pathohistological measurements were compared. By Jate's modification of c2 test results regarding correct and incorrect surgical excision in patients and control group were compared. By linear regression analysis results of tumour depth obtained by echosonographic and pathohistologic examinations were compared. Hypoechogen zone echosonographic results were used like criteria for tumour expansion. Results of tumour depth measurements are presented in Table 1. Linear regression analysis showed (R = 0.64) that echosonographic examination gave objective pictures of tumour depth. Six specimens were excluded from this examination, and only the presence of tumour cells on specimen margins were analysed. All tumours in patients were excised radically; in control group tumour cells were present on pathohistological specimens margins of six cases. In comparison p = 0.5016 was a not significant value. Success of 100% of specimens correctly excised in operated patients is the success which is very close to success of Moh's micrographic surgery (by Fleming only 1% of tumour relapse in a five-year follow-up period) [8]. Result of 13.33% of incorrect excision in control group is close to results obtained by Leshin and al [9]. Result of p = 0.05016 is not statistically significant, but is very close to statistically significant values. This might require future examinations in a larger group of patients. Results of R = 0.64 correlate with results obtained by Hoffmann [3], because they show that highfrequencies ultrasound examination gives an objective picture of skin ...