Twofield experiments were conducted at Abo hammad region Sharkia Governorate, Egypt during 1999/2000 and 2000/2001 seasons to detect the relationships between N, P, K, NP, NK, PK and NPK fertilization as independent variables and some quantity and quality characters of flax variety Giza 8 as dependent variables. The quantity characters were seed, oil, straw and fiber yields and the quality characters were N, P and K uptake in both seed and straw. Simple correlation, multiple regression and stepwise regression analysis were used to detect this relationship and the results obtained can be summarized as follows: I - Quantity characters: 1- Result of simple correlation analysis indicated that the heights significant positive correlation was found between N fertilization and each of seed, oil, straw and fiber yield with r-values were 0.858,0.782,0.765 and 0.607, respectively. Significant and positive correlation was found between phosphorus fertilization and each of seed, oil and straw yield except fiber yield. On the other hand, the r-values between potassium fertilization and each of seed, oil and straw yields were not significant but it was significant with fiber yield. 2- Result of multiple regression analysis cleared that the relative contribution for N, P, K, NP, NK, PK and NPK fertilization were accounted by 80%, 50.7%, 68.6% and 69.4% from the total variation of seed, oil, straw and fiber yields, respectively. 3- Result of stepwise regression analysis revealed that the N fertilization was the heights factor contributing in the total variation of seed, straw and fiber yield with R² being 73.7 %, 58.5% and 65.5 %, respectively. On the other hand, the NP fertilization was the height factor contributing in the total variation of oil yield with R² being 40.5%. II - Quality characters: 1-  Result of simple correlation analysis indicated that the heights significant positive correlation was found between N fertilization and each of N uptake in seed and straw, P uptake in seed, K uptake in seed and straw with r-values were 0.773, 0.845, 0.894, 0.899 and 0.630, respectively. Significant and positive correlation was found between phosphorus fertilization and each of P uptakes in straw, P uptake in seed and straw except N uptake in seed and straw and P uptake in seed. On the other hand, r-values between potassium fertilization and each of N, P and K uptake in straw were significant except N, P and K uptake in seed. 2- Result of multiple regression analysis cleared that the relative contribution of N, P, K, NP, NK, PK and NPK fertilization were accounted by 62%, 86.1%, 86.7%, 41.4, 87.4% and 61.3% from the total variation of N, P and K uptake in flaxseed and straw, respectively. 3- Result of stepwise regression analysis revealed that the N fertilization was the heights factor contributing in the total variation of N uptake in seed and straw, P uptake in straw and K uptake in seed with R² being 59.8%, 71.4 %, 79.9% and 80.8%, respectively. On the other hand, the PK fertilization was the heights factor contributing in the total variation of P uptake in straw with R² being 25.2%. Similarly, the NP fertilization was the height factor contributing in the total variation of K uptake in straw with R² being 46.7%.