Introduction. The grapefruit tree has a long production period. In the Jordan Valley, harvest lasts from November to March. Many Jordanian farmers tend to harvest their fruit early to get high prices, regardless of its quality. Thus, the effect of the harvesting date on fruit quality of grapefruit cv. ‘Red Blush’ was evaluated under Jordan Valley conditions for two seasons, 2002 and 2003. Materials and methods. Fruit quality of uniform 25-year-old grapefruit cv. ‘Red Blush’ trees budded on sour orange rootstock was studied during the 2002 and 2003 seasons. Fruits were harvested from October 15 in both seasons with 15-day intervals with a total of eight harvests. The studied data were total soluble solids (TSS), titratable acidity (TA), the [TSS/TA] ratio and juice percentage. Results and discussion. Fruit total soluble solids and fruit juice percentages were at a minimal level during early harvesting dates and increased with time, reaching the maximum level on January 1 for TSS and January 15 for fruit juice percentage in the first season and on December 15 and February 1, respectively, in the second season, after that TSS decreased. Fruit titratable acidity values were at maximal levels during early harvesting dates (October 15) and decreased with time, reaching the minimum level on February 1 in the first season and on January 15 in the second season. The [TSS/TA] ratio ranged from 5.5 to 6.0 between January 1 and February 1 in the first season, and between December 1 and January 15 in the second season. Conclusion. Our study displayed that Jordan Valley growers are harvesting their grapefruits much too early to provide acceptable eating quality fruits to local markets.