Sunflower (Helianthus annuus L.) is an important oilseed crop. In Pakistan, it is the third biggest source of edible oil. Every year Pakistan spends huge amount of its foreign reserves on import of edible oil and now Pakistan is the third largest importer of edible oilseeds in world after China and India. Our local production has decreased over the years and now our local edible oil production is only the 13% of our demand. To bridge the gap between supply and demand of edible oil in Pakistan, government has to focus on Sunflower crop. For increasing the sunflower production new and improved local sunflower hybrids should be developed. Information of Genetic diversity study is a prerequisite for designing any breeding program. In the first experiment genetic diversity among 109 sunflower lines was estimated at morphological, bio-chemical and molecular level. For morphological characterization 109 sunflower lines were evaluated during Spring-2015 and Spring-2016 at National Agricultural Research Center, Islamabad following Augmented Design. The studied genotypes showed significant amount of variation on the basis of results obtained by cluster analysis and Principal component analysis. SDS-PAGE technique was used to study the variability among the sunflower genotypes at bio-chemical level. Genetic variability at molecular level was studied using SSR markers. Morphological and molecular based characterization showed considerable amount of genetic variation among the studied sunflower genotypes, while these genotypes showed less than 3% dis-similarity through SDS-PAGE based bio-chemical genetic study. The second experiment was for the identification of heterotic groups among the studied material. Heterotic groups were identified by combing the morphological and molecular data sets as, combining different data sets has been found useful in increasing the resolution of experiment. Two major clusters one of CMS and maintainer lines and other of restorer lines were observed. Six sub-groups in each major cluster were observed and one best performing genotype from each subgroup was selected. In third experiment, 12 parents (6 CMS and 6 Restorer) selected from heterotic groups was crossed in LxT mating design during autumn, 2016 to develop crosses and study the efficacy of identified heterotic groups and gene action. 36 crosses developed along with their parents and checks were sown in Randomized Complete Block Design (RCBD) at two locations (NARC and URF) during spring-2017. Three best performing hybrids (RHP-41 x CMS-HAP-56, RHP-71 x CMS-HAP- 111, RHP-71 x CMS-HAP-12) were found to be best for seed yield and oil contents over three check hybrids and four best combining parents i.e., CMS-HAP-12, CMS-HAP-56, RHP-41 and RHP-71 were also identified. Results of our study showed that heterotic grouping among sunflower could be developed and strengthened on the basis of morphological and SSR markers to pace up the hybrid development in Sunflower.