Lectins are carbohydrate-binding proteins commonly used in the study of glycoprotein expression in mammalian hearts. However lectins have received little use in fish models and non-models species. We hypothesize that lectin binding may reveal specific and differential patterns of glycoprotein expression in fish hearts. Here, we determine the binding patterns of commonly used lectins, including wheat germ agglutinin (WGA), Ulex europaeus agglutinin (UEA lectin), Bandeiraea simplicifolia lectin (BS lectin), Concanavalin A (Con A), Ricinus communis (RCA), and Lycopersicon esculentum lectin (tomato lectin) in zebrafish and giant danio hearts. Our results show that WGA stained fish cardiac myocyte borders in patterns similar to that seen in mammalian hearts, with staining markedly stronger in the fish compact hearts. Con A showed broad and strong staining in fish ventricles. Interestingly, BS lectin reacted poorly to a number of fish species including zebrafish, pearl danio, common koi, goldfish, and Buenos Aires tetra. By contrast BS lectin strongly stained coronary vessels of giant danio, and several pleco and gourami species. Importantly, enhanced BS lectin biding to vascular endothelium compared to endocardium allowed for 3D coronary angiography in the giant danio, and for quantitation of vascular reconstruction during regeneration. Differential lectin reactivity was further observed in developing zebrafish hearts. In conclusion, our study demonstrates that lectins are simple but important tools for studies in model fish species, and in adult and regenerating giant danio heart.