Based on the fishery resource survey data collected in Haizhou Bay and its adjacent waters in spring and autumn from 2013 to 2022, we evaluated the statement and change trend of the ecosystem health of Haizhou Bay using the fish-index of biotic integrity (F-IBI), considering many ecological parameters and attributes such as fish species composition, tolerance, trophic guild, and reproductive guild. The results showed that eight metrics were retained as F-IBI of Haizhou Bay in each season. The F-IBI scores of Haizhou Bay in spring and autumn ranged from 18 to 51 and from 24 to 54, respectively. The ecosystem of Haizhou Bay was basically at "fair" or above levels in spring, while fluctuating around "fair" level in autumn. Generally, the health statement of Haizhou Bay ecosystem in spring was better, and the F-IBI scores showed a gradually decreasing trend in fluctuation. The condition of fishery resources in Haizhou Bay were poor, with an increased proportion of tolerance and omnivorous fish species. Fishery resources in Haizhou Bay were under various pressures such as overfishing and climate change, and scientific and reasonable measures should be taken to protect and restore the ecosystem of Haizhou Bay.