The performance of four varieties of Egyptian cotton, two of them belong to the extra long staple category i.e. Giza 87 and Gin 88, and two belong to the long staple category i.e. Giza 88 and Gin 89 were evaluated for early maturity using seven methods of earliness measurements and seed cotton yield during the 2000 and 2001 sea. sons. Date of flowering was recorded daily, and the average number of flowers for 10 plants per week was calculated to construct curves for weekly flowering. Plants of each variety was picked at weekly intervals to calculate the percentage of crop harvested (PCH%). Moreover, this study included five measurements of earliness: i.e. position of first fruiting node (PEN), day to first flower (OFF), earliness percentage (Er %), mean maturity date (MMD In days) and production rate index (PRI). Simple correlation coefficients among five of the measurements and with seed cotton yield were calculated. Rate of weekly flowering followed a normal distribution curve. Effect of varieties on number of flowers showed significant differ­ences in some weeks after planting. Also the effect of growing season was significant in some weeks. The effect of varieties x growing season was significant in two weeks after planting (18 and 21). The highest number of flowers was produced at the 15. 16 and 17 weeks after plant­ing. The maximum average rate of flowering was found at the sixteen week after planting (15/7: 21/7) in all varieties. Varieties differences were significant in the 1" and 2^r4 picks. The rate of PCH followed a nor. mat distribution, while the effect of growing season was significant In the (1, 6, 7, 8 and 9) picks. The effect of interaction between cotton varie­ties and growing season was significant in 4'" pick only. Giza 88 and Gin 89 were the earliest followed by Gin 86 while Giza 87 was the latest. The effect of varieties was significant for all the studied traits. While the effect of growing season was significant for studied trails except day to first flower (OFF), also the effect of interaction between varieties x growing season was significant for (MMD) and (PRI) traits. Gin 89 gave the highest seed cotton yield (12.48 K/F) while Gin 87 was to lowest (10 K/F). Four of the measurements of earliness, (PEN. Er %, MMD and PRI) were significantly correlated therefore, any of them could be used with confidence to estimate earliness.