Nasal administration of corticosteroids is indicated in the treatment of acute and chronic inflammatory diseases of nasal mucosa. A disadvantage of registered drugs in the form of drops or nasal spray is short retention time on the application site. Therefore, new drug delivery systems with prolonged contact with nasal mucosa and controlled release of the drug at the site of administration are being developed, such as polymeric drug loaded microspheres. In this diploma thesis, sodium dexamethasone phosphate (SDP) loaded microspheres based on pectin and hypromellose for nasal administration were prepared by spray-drying method. The aim of this study was to investigate the influence of pectin to hypromellose weight ratio in the polymeric matrix on the obtained microspheres' properties which are important for nasal powder systems. SDP loaded microspheres with pectin to hypromellose weight ratio of 1:0, 1:1, 1:2 and 2:1 were successfully prepared by spray-drying of SDP solution at concentration of 0.01% (w/v) and polymer(s) solution at total concentration of 0.5% (w/v). Process yield ranged between 46 and 64%. Obtained microspheres are characterized by mean diameter from 3.13 ± 0.46 to 3.82 ± 0.32 μm. A similar particle sizes distribution is observed in all microspheres samples with about 80% of particles having a diameter smaller than 5 μm. Microspheres were characterized by drug loading from 1.83 to 2.24%. In the swelling process, microspheres with higher pectin content in comparison to hypromellose showed a higher swelling degree, while the incorporated drug had no significant effect on the swelling properties. All microsphere samples absorbed significantly less SNF volume per mass unit in comparison to the purified water. Rapid initial drug release during the first 60 min (77.0 ± 2.6 - 89.4 ± 5.9%) was observed, followed by a slower release phase. No significant difference was observed in the in vitro release rate between different microsphere samples.