The purpose of this study was physical and chemical analysis of watermelon seeds (waste) the markets Study of optimize replacing watermelon seeds (waste) by peanuts in thai foods process and consumer acceptability indicated of products. Result showed that physical and chemical analysis of watermelon seeds (waste) the markets as follows : Aw =0.37±0.06 L* a* b* value 60.88±0.13 10.65±0.05 and 41.02±0.06 respectively and moisture content 1.19% protein content 10.97% fat content 0.22% crude fiber content 6.48% ash content 3.26% and carbohydrate content 77.88%. Result showed that the best formula was mussaman curry was replacing watermelon seeds (waste) by peanuts 100%. Product have orange yellow colour be similar to product in markets and less than fat content 1.65 times protein content and ash content more than 1.59 2.65 respectively.The shelf life meagerly 2 months and consumer acceptability like moderately mussaman curry powder and mussaman curry product. Result showed that the best formula was kao tung na tang crispy rice sticks and shrimp dipping replacing watermelon seeds (waste) by peanuts 100%. Product have orange yellow colour more than product in markets. And more than fiber content and protein content 1.31 1.51 times less than fat content and ash content 1.24 1.32 respectively. The shelf life meagerly 2 weeks and consumer acceptability like moderately product. Result showed that the best formula was panaeng curry powder replacing watermelon seeds (waste) by peanuts 100%. Product have bright orange colour. The shelf life meagerly 4 months and consumer acceptability like very much product. Result showed that the best formula was sai kow griep pag mor replacing watermelon seeds (waste) by peanuts 100%. Product have dark brown more than product in markets. And less than moisture content fat content and fiber content 2.17 6.61 and 6.46 times more than carbohydrate content and ash content 68.24 4.10 respectively. The shelf life at -18 ๐C and consumer acceptability like moderately product.