Technical Abstract: A set of recombinant inbred (RIL) cucumber lines (Cucumis sativus L.) is being released by U. S. Department of Agriculture, Agricultural Research Service as genetic stock and for breeding purposes. These RIL were developed in conjunction with mapping experiments that sought to identify molecular markers linked to economically important traits (i.e., yield components) controlled by quantitative trait loci (QTL) in F3 families derived from a GY-7 x H-19 mating. These F3 families were self-pollinated to produce 168 RIL that were assessed in two years in field tests at the University of Wisconsin Experiment Station, Hancock, WI. A RIL-based map was constructed using 14 single sequence repeats, 24 sequence characterized amplified regions (SCAR), 27 amplified fragment length polymorphisms, 62 random amplified polymorphic DNA, 1 single nucleotide polymorphism, and 3 economically important morphological [F (gynoecy), de (determinate habit), ll (little leaf)] markers. This map consists of seven linkage groups spanning 706 cM with mean marker interval of 5.6 cM. Recombinant inbred lines, parents and F1 were evaluated in one location in 1999 and 2000. For evaluation, RILs were arranged in randomized complete block design with three replications (12 plants/plot) per location. Data were collected on plant habit, days to anthesis, sex expression, leaf type, number of lateral branches originating from the mainstem, and fruit number and fruit length/diameter ratio. Considerable variation in the traits examined among RIL was observed in plant habit (determinate and indeterminate), earliness (45 to 57 days to anthesis), sex type (gynoecious and monoecious), lateral branches (1 to 9), fruit number (1 to 7 fruit per plant), and L:D (2.8 to 3.1). Mulitple branching lines were identified that produced commercially acceptable fruit. The RIL described can be used in conjunction this map to identify additional qualitative (e.g., disease resistance) and quantitative (e.g., fruit yield and quantity components) traits and for use in the development of inbred backcross lines for extensive genetic analyses (e.g., fine mapping).