The Southern Coastal Orissa Is Endowed With A Number Of Multi-Mineral Placer Deposits, Which Are Not Only The Source Of Uranium And Thorium For Nuclear Industry But Also The Source Of Radiation Exposure To The Environment. Thus, The Present Study Is Focused On Field Occurrence And Radioactivity Of Heavy Minerals Sand, Possible Source Rocks, Radiometric, Dosimetric And Environmental Radioactivity Studies Along The Gopalpur-Chhatrapur-Rushikulya Beach Placer Deposits Of Southern Coastal Orissa. Field Observations Showed That Marine Waves Played A More Dominant Role Than Aeolian Action In Concentrating The Heavy Minerals Sand In Different Beach Morphologies Viz. Shore, Beach Bar, Berm, Intermediate And Rear Dunes, Except The Frontal Dune. Field Radiometric Survey Suggested That The Heavy Minerals Sand Are More Abundant In Berm And Dunes Due To Marine Action, Which Inferred That Supply Of This Sand, May Be Greater In Past. Petrographic Study Of Surrounding Eastern Ghats Rocks And Separation Of Individual Mineral Fractions Followed By Their X-Ray Diffraction Identification Suggested That Granitoid Is Possibly The Main Contributor Of Monazite. The Other Heavy Minerals May Have Their Sources In The Lithounits Of Charnockite, Khondalite And Gneisses. Radiometric Study Showed That The Thorium Rich Mineral (Monazite) Is Predominant In These Areas And Dunes Are The Potential Zone For The Radiogenic Heavy Minerals. The Eth/Eu Ratios Of Beach Sand Samples Suggested An Oxidizing Condition For The Beach Placer Deposits. Radon-Thoron Study Showed That The Higher Concentration Of Thoron In The Dwellings In All The Seasons Points To The Importance Of Thoron Which Is Widely Dispersed Throughout The Study Area. Seasonal Variation Of Indoor Radon And Thoron Exhibited High Values In Winter And Low Values In Both Summer And Rainy Seasons. The Inhalation Dose Was Not Higher Than Those Found Elsewhere In India, Whereas The External Gamma Dose Is Somewhat Higher Than The Average External Gamma Radiation Dose Obtained In Various Parts Of India. The Results Of Radioactivity Dose Rates Revealed That Gopalpur And Rushikulya Beach Placer Regions Can Be Considered As Natural High Background Radiation Areas, Whose Main Source In The Beach Sediments Is 232th. The Radium Equivalent Activity And Radiation Hazard Index Also Pointed That The Soil Of These Areas May Not Be Usable As A Construction Material Without Proper Remediation But A Possible Mineral Exploration Is Suggested Which Would Be Greatful.