In Nigeria, the kernel of a ripe mango fruit which is approximately 35-60% of the absolute mango fruit weight still remains a waste and contaminant after the pulp consumption. This could be as a result of lack of adequate information available on the different predominant varieties. Current research was therefore carried out to determine the anti-oxidant and phytochemical properties of four selected varieties of mango kernel seeds (German, Fazli, Cherry and Safeda) using standard techniques. The radicals scavenging activity of the extracts were performed using 1,1-diphenyl-2-picrylhydrazyl (DPPH)-radical scavenging assay, and 2,2′-Azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS)-radical scavenging assay, Lipid peroxidation inhibition assay, Super-Oxide Dismutase assay, Glutathione Reductase assay and Catalase assay. Determination of Vitamin C was done using titrimetric method and all compared using standard methods. Phytochemical and biochemical screenings showed the presence of Saponin, Flavonoids, Alkaloids, Phytate, Oxalate, Heamaglutinin, Phenol, Cardiac glycoside, Terpenoids and Tannin. The quantitative analysis result indicated that tannin (3.078%), phenol (8.091mg/kg), and oxalate (0.108mg/100) were present in higher concentration in the seed kernel of Cherry compared to others, while terpenoids (16.00%), cardiac glycoside (8.845%) and hemaglutinin (3.558mg/kg) were present in higher concentration in the seed kernel of German compared to the others. Phytate (0.927mg/100) and flavonoids (5.594%) were higher in safeda whereas saponin (4.00%) and alkaloids (4.781%) where higher in fazli. Ferric Reducing Antioxidant property (FRAP) results showed that ripe mango kernel of Fazli exhibited highest Ferric Reducing power of 61mg/ml concentration and absorbance of 0.510 at wavelength of 593nm using UV- Spectrophotometer. This study therefore showed that different varieties of mango seed kernel contain varying amount of pharmacologically dynamic substances that are valuable and available as antioxidants, potential additives and other therapeutic purposes.