Objective: A color change indicator card for visual detection of fresh sea bass was studied. Methods: Using 1% Papaver rhoeas L. pigment as indicator and methyl cellulose gel as film-forming substrate, the label was made to study the color difference（ΔE） of the indicative label. The response of ΔE to pH was studied. Meanwhile, the content of TVB-N, TBARS, pH value, indicator label color and the linear relationship among these factors and ΔE under 4 ℃ sea bass preservation were determined. Results: The results showed that the indicator label had good discoloration effect in the range of pH 2.0~9.0. The TVB-N of sea bass and indicator ΔE were significant. and the color change was pink-purple-chartreuse-sepia. Chartreuse means superior, and yellowish brown means qualified. When the intelligent label reached sepia, the sea bass was inedible. The color of indicator label could be clearly distinguished by naked eye. Conclusion: The results showed that the pigment indicator label could be used as the indicator label of sea bass freshness.