In this study, separation of chemical compounds using Thin layer chromatography technique revealed close relationship between the studied members of the newly constructed family Amaranthaceae Juss. (s.l.). 68% of the calculated affinities between the studied species are above 50% which is an indication for close relationships. 90% is the chemical affinities reported between Chenopodium murale and three species of the genus Amaranthus despite of their great morphological diversity. Among the selected members of the chenopodiaceae, Chenopodium murale and Suaeda monoica are the most closely related species to all of the studied Amaranthaceae . 60%-88% and 54%-88% chemical affinities were reported for the two species with the Amaranthaceae members respectively. GC-Mass analysis of methanolic extracts of the studied species identified 20 compounds common between different species. 9,12-Octadecadienoic acid (Z,Z)-,2-hydroxy-1 and 7-Hexadecenal,(Z)- are the major components common between Amaranthus graecizans, Digera muricata Aerva javanica Gomphrena celosioides of the historical family Amaranthaceae and Suaeda monoica Salsola vermiculata Chenopodium murale Cornulaca monocantha of the historical family Chenopodiaceae, Most of the identified compounds are of pharmaceutical importance such as antioxidants, anti-inflammatory , and Anti-cancerous. KEYWORDS: Chemical affinity; TLC; GC- Mass analysis; Amarancaceae; Chenopodiaceae