Prior research on firm performance at aggregate level may not be applicable for the firms classified on group affiliation and listing. This is because there is substantial difference in the structure of these firms belonging to each category. We examine the difference in the structure of the Indian firms in each category by using Logit regressions. Further, we analyze firm level data for the period 2007-08 to 2009-10 using accounting based firm performance measure Return on Assets (ROA) since our data includes unlisted firms as well for which market based information is not available. We include the variable square of size along with size (and other variables) to account for non-linear relationship between the size and ROA. The results of cross section regressions show that ROA and size have inverted U-shape relationship for all categories of firms except BG unlisted category. Further we find that the impact of firm level variables on ROA is different in each category of firms.