Aq. solns. of biodegradable chitosan matrix and multicomponent mineral fertilizers were spray-dried under lab. conditions at 170 degrees C to prep. slow-release fertilizers. The prepd. fertilizers showed lower release ability (31.0-50.1% after 60 min) than the original fertilizers (92%) but did not meet the std. requirements for the slow-release fertilizers. The resulted powders were studied for their structure by x-ray diffraction, IR spectroscopy and SEM.