This study aims to analyze the relationship between demand and supply of skipjack tuna at the Fish Auction Place (TPI) Sedati, Sidoarjo Regency. Data were collected through observations, interviews, and literature studies. The research results indicate that fish prices, community income, and supply costs significantly influence the demand and availability of fish at TPI Sedati. Proper stock management is necessary to maintain a balance between demand and supply to improve fishermen's welfare and market efficiency.