Technical Abstract: Inheritance patterns of sugar and organic acid contents of ripe berries in a tetraploid x diploid table grape cross population were investigated in two successive years. The population segregated for three different ploidy levels: dipolids, triploids, and tetraploids. Sugar content in tetraploid progeny was significantly higher than that in the diploid progeny. Transgressive segregation for sugar content was observed in all the three ploidy levels in the progeny population. The broad sense heritabilities (H2) of glucose, fructose and total sugar contents ranged from 0.68 to 0.79. The tetraploid progeny had the highest H2, followed by the diploid and triploid progeny. The sugar contents appeared additive as the ploidy level increased. All the sugar contents were highly and positively correlated with each other. Malic acid in the diploid progeny population was significantly higher than that in the polyploidy progeny populations, and the tartaric acid in the triploid progeny was significantly higher than that in diploid and tetraploid progenies. H2 of organic acids ranged from 0.71 to 0.91, with the tetraploids having the highest mean H2. In contrast with the sugar content, the total acid content was decreased as the ploidy level increased. Positive correlations were also observed among the contents of various acids, but the correlation coefficient was low between tartaric acid and malic acid and moderate between tartaric acid and the total acids. The tetraploid maternal parent was more important in determining tartaric acid content of triploid and tetraploid progenies. A large range of variation was observed for both sugars and acids in the triploid and tetraploid progenies than in the diploid progeny.