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The parameters for microdischarges of plasma medicine in air and argon vortex flows at atmospheric pressure for different shapes of electrodes (outlet nozzle and axis electrode diameters ratio set) have been investigated. The current-voltage characteristics of the designed systems have been analyzed, the parameters of the generated jets plasma have been investigated by means of the optical emission spectroscopy, and the form of plasma jets has been studied by using video camera. Keywords: microdischarge, gliding microdischarge, microjet, glow discharge, emission spectroscopy. DOI: 10.1515/chem-2015-0043received February 07, 2014; accepted May 30, 2014. 1 Introduction Microdischarge plasma generation is considered to be one of the most promising areas of non-equilibrium plasma chemistry today and can be applied in different fields: for the environmental protection, in biology and biomedicine, as an ultraviolet and vacuum ultraviolet intense source, and for the surface activation and films deposition. Currently there is no full understanding of the microdischarge physics nature, and therefore it is impossible to do the detailed analysis of their parameters. Microdischarge plasma is characterized by significant changes of the excited states distribution function and ions and electrons energy in a relatively short time. It is possible to use such discharges as the sources of reactions active components.The medical area is interested in the different microplasma systems to ensure by their ability to generate low-temperature non-equilibrium atmospheric pressure plasma (NAPP). The electron temperature in NAPP is a few eV, which is usually sufficient, to initiate a group of chemical reactions including – proteins, cell membranes and DNA modification; and producing radicals. At the same time, the heavy particle temperature is close to room temperature; therefore the plasma treatment does not destroy temperature sensitive biological tissues. The disinfection, decontamination and sterilization processes that uses active plasma particles (radicals, charged particles, excited particles, UV radiation) occurs quite rapidly under such conditions. Experiments have shown several seconds to several minutes of the plasma treatment is necessary for different types of viruses and bacteria neutralization on surfaces and in aqueous solutions. The following applications of plasma systems in medicine are known from the literature [1-3]: sterilization, cancer cells destruction, blood coagulators (to stop bleeding), and wound healing, whitening and cleaning teeth. It was shown that plasma usage in combination with well-known traditional medical methods significantly increases its efficiency. Currently, there are two main applications of NAPP for disinfection, decontamination and sterilization. For the first application, the plasma generation is remote, and the products of its afterglow are delivered to the biological tissue in a loop. The therapeutic effect is probably provided by the neutral particles and radicals with long-term existence, while the majority of charged particles disappear outside the plasma generation zone. Usually, in order to avoid plasma instability, the work should be carried out with helium or argon diluted gases, and the discharge is doped with just a few percent of molecular