Fish waste is a major by-product of fish processing industries. Sin croaker (Johniecop sina) waste could be a valuable source of collagen and utilizing such waste will reduce pollution associated with fish processing industries. The objective of this study is to determine the physico-chemical characteristics of sin croaker waste collagen extracted using 0.5 M acetic acid as a function of extraction time which were 3 and 5 days. The extracted collagens were also compared with the commercial collagen. Results showed that extraction at the duration of 3 and 5 days produced 2.74 and 3.35% yields of collagen, respectively. Both collagens were most soluble at low pH (pH 1-2) and low salt concentration (2% NaCl). Differential Scanning Calorimetry (DSC) analysis showed that the extracted collagen had good thermal stability as it denatured at 31.31°C and 32.10°C, respectively. Commercial collagen denatured at 30.60°C. Sodium dodecyl sulfate gel electrophoresis (SDS-PAGE) indicated that both collagens are of Type I due to the presence of α1, α2 chains, β and γ components. Commercial collagen showed only smeared band. Thus, it is concluded that sin croaker collagens extracted at the duration of 3 and 5 days exhibited similar characteristics and are of equally good quality.