The present investigation was conducted using six flax genotypes with their 15 F₁ crosses grown under two environments (Giza Exp.Station, Giza Governorate and Ismailia Exp.Station, Ismailia Governorate) to determine combining ability and gene action of some agronomic flax characters in these entries (parents and their crosses). In 2007/08 season, the six parents {P₁ (S.541-A/5), P₂ (Sakha 3) , P₃ (S.435/11/10/3), P₄ (Gentiana), P₅ (Elona) and P₆ (Escalina)} and their 15 progenies were evaluated in a randomized complete block design with three replications at the two above- mentioned locations. High ratio of GCA/SCA revealed that additive played greater role than non-additive genetic effects in the inheritance of straw weight and its two important components (plant height and technical stem length) as well as seed weight and its two important components (No. of capsules per plant and 1000-seed weight) under the two environments and combined analysis. On the other hand, the non-additive genetic effects played an important role in the inheritance of No. of basal branches per plant. Mean squares of interaction between environment and both types of combining ability for most studied traits revealed that the magnitude of both additive and non-additive types of gene action varied from environment to another. Whereas the non-additive genetic effects are more influenced by drought environment than additive effects in each of straw weight, plant height, seed weight and No. of capsules per plant. In contrast, additive genetic effects were more influenced by environment than non-additive effects in both technical stem length and No. of seeds/capsule. The two parents, P₁ and P₃ showed significant positive g_i effects for straw weight, seed weight, No. of capsules per plant and 1000-seed weight in both environments and the combined data. For S_ij effects, the two crosses, P₁xP₄ and P₁xP₆ for straw weight in addition the two crosses, P₁xP₅ and P₂xP₃ for seed weight and 1000-seed weight included low x high general combiner parents. Therefore, these crosses are suitable in breeding program for increasing the previous characters. Concerning drought tolerance, P₃ for each of straw weight, seed weight, No. of capsules and 1000-seed weight; P₄ for plant height; P₅ for technical stem length and P₁ for each of plant height, No. of basal branches per plant and 1000-seed weight exhibited high yielding ability with tolerance to drought. Also, the cross, P₄xP₅ exhibited high yield potential with moderate tolerance to drought for each of straw weight, plant height and technical stem length. While, the cross P₁xP₅ only exhibited high yielding potential and stress tolerance for all seed characters. In the meantime's this cross (P₁xP₅) showed high SCA effects for seed weight and its two important components. Hence the two crosses, P₁xP₅ and P₄xP₅ may be useful as potential breeding material for developing genotypes tolerant to sandy soil conditions for seed and straw weight, respectively.