<p><i>Foeniculum vulgare</i> Mill., commonly known as fennel, is a medicinal plant belonging to the family-Apiaceae. This plant has been used in traditional medicine against wide range of diseases. It is present both in wild as well as in cultivation. Our study is based on wild and cultivated forms of fennel from the Jammu region. Both were studied for the reproductive efficiency and GC-MS analysis of the ethanolic extract of their seeds. With respect to sexual reproductive output, wild form revealed higher percentage fruit set (92.22%) in comparable to cultivated (82.09%). This might be due to the higher diversity of insect’s visitation on wild form. But the size of seeds in wild fennel are comparable smaller than the cultivated one. By analyzing GCMS data, a total of 106 different compounds have been identified in which 57 compounds exhibit similarities in both wild and cultivated forms and rest are different. The most abundant compound is 6-Octadecenoic acid i.e. 59.19% in wild and 42.36% in cultivated. Such high percentage area under peak has not been reported earlier in the fennel. Also, the concentration of anethole, principal compound in the fennel, was found to be in negligible (≤ 1%) amount in both forms which is a new finding from Jammu region. In concern to wild and cultivated form, among 55 phytoconstituents which exhibits similarities in both forms, all showed higher percentage area under peak in cultivated in comparable to wild except four compounds para-Anisaldehyde diethyl acetal, 6-Octadecenoic acid, Propanamide, N-ethyl-N-(3-methylphenyl) and Stigmasta-5,22-dien-3-ol, acetat (3. beta.). This might be attributed mainly to the impacts of domestication or selection pressure on the biosynthesis of the constituents.</p>