Molecular phylogenetic and traditional morphometric methods were applied to examine six Palaearctic taxa of the taxonomically difficult tachinid fly genus Dinera Robineau-Desvoidy (Diptera: Tachinidae), with particular reference to D. carinifrons (Fallén) and D. fuscata Zhang and Shima. Results of a phylogenetic analysis based on the mitochondrial markers 12S and 16S rDNA and multivariate statistical analyses of 19 morphometric characters were used to delimit both species. A lectotype was designated for D. carinifrons to stabilize the nomenclature in the group. Dinera carinifrons has a transpalaearctic distribution and is present in Central Europe, especially in high altitudes of the Alps. It differs from the similar and closely related D. fuscata in that it has a slightly larger body size, a dense greyish microtrichosity on the body, and different head proportions. Dinera fuscata, as delimited here, is widespread in the Palaearctic region, including Europe. Slight differences in both molecular and morphometric characters were found between western (Europe and Iran) and eastern (China and Japan) populations of D. fuscata, which are interpreted as an intraspecific variation. Differential diagnosis between D. carinifrons and D. fuscata is provided in the form of a revised portion of the determination key to the Palaearctic Dinera by Zhang and Shima (2006). CETPO project CZ.1.07/2.3.00/20.0166 (partly).