A quantitative relationship was found between the relative fluorescence intensities of certain metal chelates of some quinolone antibacterials and their physicochemical parameters namely: the pKa1 (corresponding to the ionisation of the 3-carboxylic group) and the calculated stability constants of the formed chelates as well as the second order connectivity indexes (2  v), Hammett constant (  m), polar constants (F) and resonance constants (R) for the substituent at position 1 of the quinolone nucleus. The studied quinolone antibacterials are amifloxacin, difloxacin, ciprofloxacin, nalidixic acid, norfloxacin, lomefloxacin, ofloxacin and pefloxacin and the metals involved are zirconium, molybdenum, vanadium and tungsten. Twenty highly significant regression equations were obtained and used to calculate the unreported values of  m, F and R for the substituent at position 1 of ofloxacin. Two correlation equations were used also to predict the fluorescence intensity of molybdenum chelates of the studied quinolones.