Atherina boyeri is a translocated and invasive fish species that is known to pose problems to the native fish fauna and other. In this study, twenty three morphometric properties of the sand smelt, A. boyeri population in Süreyyabey Dam Lake was investigated for the first time. Twenty three morphometric characters of samples were measured and evaluated. These characteristics were standard length, fork length, total length, body weight, pre orbital distance, eye diameter, inter orbital distance, head length, head width, dorsal fin I nose point distance, dorsal fin II nose point distance, pre anal distance, pre pectoral distance, pre ventral distance, dorsal fin I base length, dorsal fin II base length, anal fin base length, pectoral fin base length, ventral fin base length, maximum body height, caudal peduncle height, body width, caudal peduncle width. The fork length of individuals which were caught (FL) were between 5.30 and 7.30 cm, and their weight (W) were ranged between 1.12 and 3.57 g. This paper reports the first occurrence of A. boyeri from Süreyyabey Dam Lake in YeÃ ÂilÃÂ±rmak Basin.