High pollen viability with adequate quantity determine yield of hybrid seed production. Stored pollen with high viability is expected to produce high quantity and quality of hybrid seed. The aims of this research was to study the possibility of using stored pollen in hybrid seed production of cucumber (Cucumis sativus L.). The research was conducted in Pollen Laboratory, screen house (SH), and experimental station of PT. East West Seed Indonesia, Gumuk Segawe village, Ajung subdistrict, Jember, East Java from March until August 2011. The research was started with observation on the timing of receptive stigma based on color changes of petal and stigmatic surface every hour during which time pollination was also conducted. Percentage of fruit set and seed set from each pollination were observed. The research was then continued with experiments conductedin the field and SH separately. The experiment was arranged in completely randomized block design with 10 treatments in the field and 13 treatments in SH. The treatments for field experiment were combination of storage period (0, 20, 30 and 40 DAS) and pollination technique (1, 2, 3 times swabbing). The storage period for SH experiment were 0, 7, 14 and 28 DAS. The treatments were repeated 3 times. The result showed that the stigma was receptive during 07.00-13.00 h. The viability of stored pollen 20-40 DAS ranged between 0.8-4% whereas 7-28 DAS ranged between 4.8-9.71%. Fruit set from stored pollen ranged 21.23-42.42% and seed set ranged 16.89-25.26% in the field compared to use of fresh pollen 54.64 and 59.26% respectively. As for SH the fruit set ranged 30.69-63.98% and seed set ranged 18.22-35.68% from stored pollen compared 73.56% and 80.69% from fresh pollen. Reproductive succes of stored pollen in the field ranged 12.82-29.29% with averaged of 19.89% compared to that of fresh pollen, whereas in the SH used of stored pollen resulted in 10.60-25.29%, averaged 18.89% reproductive succes.Key words: empty seed, pollen viability, seed set, seed quality, stigma receptivity ABSTRAKViabilitas serbuk sari yang tinggi dan jumlah serbuk sari yang memadai menentukan produksi benih hibrida mentimun. Serbuk sari yang telah disimpan dan mempunyai viabilitas yang tinggi diharapkan dapat digunakan dalam produksi benih hibrida dengan mutu yang tinggi. Oleh sebab itu penelitian ini bertujuan untuk mempelajari kemungkinan pemanfaatan serbuk sari yang telah disimpan dalam produksi benih hibrida mentimun (Cucumis sativus L.). Penelitian ini dilakukan di Laboratorium Serbuk Sari, screen house (SH) dan lahan percobaan Production Farm PT. East West Seed Indonesia, Desa Gumuk Segawe, Kecamatan Ajung, Kabupaten Jember, Jawa Timur dari bulan Maret hingga Agustus 2011. Penelitian ini diawali dengan penentuan masa reseptif stigma yang diamati berdasarkan perubahan warna mahkota dan permukaan stigma setiap jam, dan pada saat yang sama stigma diserbuk. Pengamatan dilakukan terhadap pembentukan buah dan benih. Penelitian...