A novel host inclusion complex of cross-linking-polymeric-beta-cyclodextrin-o-vanillin furfuralhydrazone (beta-CDP-OVFH) was synthesized and characterized with IR and (1)H NMR spectra to confirm its structure. A highly selective and sensitive fluorescent determination of trace amounts of gallium was proposed based on the reaction between Ga(3+) with beta-CDP-OVFH in acetic acid-ammonium acetate buffer medium of pH 4.10. The maximum excitation and emission wavelengths were 392 and 499 nm, respectively. The linear range of this method was 1.5-330 ng ml(-1) with a detection limit of 0.44 ng ml(-1). The effect of interferences in the determination of gallium was investigated and the results showed that the same race elements such as Al(3+) and In(3+) did not interfere the determination of Ga(3+) even when their concentration is 100 times of Ga(3+), the host reagent had quite high capacity of identifying Ga(3+). This method was successfully applied to the determination of trace amounts of Ga(3+) in artificial and semiconductor samples.