Our purpose was to determine cultivar and culture system effects on yield and postharvest quality of greenhouse tomato Lycopersicon esculentum. Nine tomato cultivars were sown into rockwool cubes on 2 Feb. 1994. The plants were transplanted into peat bags or nutrient film (NFT) systems on 9 Mar. Harvesting began on 2 May until 26 Sept. for a total of 21 harvest weeks. Fruit yield, rejected or nonmarketable fruit and four fruit quality indicators (fruit texture, color, titrable acidity, and soluble sugars) were measured during the harvest period. In addition, these indicators were further evaluated every 7 days during 28 days of storage at 20C and 90% RH for `Trust' and `Cencara', a long shelf-life cultivar. `Bounty', `Panther', and `Cencara' gave higher yields on rockwool but `Irazu', `Correct', `73-53', and `Medallion' gave better results on NFT. `Trust' produced the best yield for either rockwool or NFT. Culture systems (peat bags or NFT) did not affect fruit quality. `Cencara', which is a long shelf-life cultivar, kept high texture quality until 28 days of storage. However, titrable acidity of `Cencara' was higher and soluble sugars content was lower than that of `Trust'