Surveys were conducted to detect and determine the incidence of Tomato spotted wilt virus (TSWV) in lettuce plants by serological and molecular assays in the winter of 2007 and 2008. A total area of about more than 400.000 plants was monitored in 31 fields in Adana and Mersin provinces. Of these, 336 showing virus-like symptoms were tested using DASELISA for the presence of TSWV infection and ELISA positive lettuce samples were confirmed by RT-PCR using TSWV S RNA gene specific primer pairs. Based on these results, the incidence of TSWV in tested lettuce samples was found to be 1.2%.© 2010 Friends Science Publishers