Honeybees (Apis mellifera L.)  live   in a wide geographic range preoccupy various climatic regions. Apis mellifera jemenitica Ruttner is variable morphometrically in size, hair length, color, and ecological adaptions. The present study was conducted through 2024 season, in the Apiary of Department of Plant Protection, Faculty of Agriculture, Al-Azhar University. The main target to improving honeybees of Yemeni, Apis mellifera jemenitica by crossing with a drone of Carniolan race and the morphological characters were measured. The instrumental insemination was according to the mentioned target of the present work. Data were subjected to analysis of variance using “SPSS" computer statistical program. The data obtained for the mean values of thirteen morphometric characters were significant. The increasing percentage change in the morphometrical parameters in hybrid after crossing inheritance between Yemeni and Carniolan races were higher, 9.21% for the length of proboscis, 8.53 for the width of the first wax mirrors, 7.70% for the tibial length, 6.83% for the length of hindwing, 6.06% for width of the hindwing,5.53 for width of the third sternum, 5.08% for length of the first wax mirror, 4.67%for the width of basitarsus, 4.26% for the length of basitarsus, and 4.04% for the tibial width. The least value of increasing was 2.48% for the length of the third sternum. The F1 generation exhibit a positive heterosis for proboscis length, forewing length, length and width of hindwing, length and width of hind tibiae, basitarsus length and width, length of the first wax mirrors, and length of the third sternum.