Purple sweet potatoes are widely used as a source of antioxidants and natural dyes in food products. This study aimed to evaluate the physicochemical properties and antioxidant activity of substitution of tapioca flour with purple sweet potato flour. The treatments employed were the substitution of tapioca flour (T) with purple sweet potato (P) with a ratio of 20:0; 15:5; 10:10; 5:15, and 0:20 (meat weight basis). Variables measured were nutrient content, pH, cooking loss, water holding capacity (WHC), Colour, anthocyanin content, and scavenging activity. The results showed that the substitution of tapioca with purple sweet potato did not affect the nutritional content except for crude fiber content, and pH of chicken meatballs. However, it increased the cooking loss, anthocyanin content, redness, and scavenging activity, and decreased the WHC and brightness (L*). It could be summarized that the substitution of the tapioca flour with purple sweet potato increased the functional properties of the chicken meatball without any changes in nutritional, pH value, and physical properties of the chicken meatballs.