The present study was undertaken to assess the genetic variability, heritability and genetic advance in F₁ and F₂ generations of ten China aster (Callistephus chinensis) hybrids developed through line × tester mating design. A comprehensive evaluation of growth, floral and yield-related traits was conducted to understand the extent of variability and inheritance patterns. Significant differences were observed among hybrids for all the studied traits. High phenotypic and genotypic coefficients of variation (PCV and GCV), coupled with high heritability (>90 %) and genetic advance, were recorded for plant height, plant spread, number of branches per plant, flower diameter, number of flowers per plant and flower yield per plant and per hectare. Particularly, hybrids H4, H5 and H6 showed superior performance in both generations, indicating their potential for further selection and genetic improvement. The F₂ generation exhibited increased variability due to segregation, with higher expression of additive gene action. Yield and floral traits, especially the number of flowers, flower diameter and flower weight, demonstrated high heritability and genetic advance, suggesting scope for effective selection. The study concludes that traits governed by additive genetic control can be improved through simple selection in segregating populations and promising hybrids identified can be utilised in future breeding programs aimed at improving China aster productivity and floral quality.