In this study, microstructural and mechanical characteristics and corrosion resistence of the UNS S32906 super duplex steainless steel were investigated. The gas tungsten arc welding technique with direct current electrode negative polarity was used. Also the Sandvik 29.8.2.L was used as the filler metal. Heat input is one of the most important factors which affects welding structure and properties. In order to evaluate the influence of heat input, welding was carried out in 1.19, 1.46 and 1.87 Kj/mm. microstructure of base metal and weldments was examined using optical and scanning electron microscopes. EDS technique was used to understand how the alloying elements are distributed into the ferrite and austenite phases. Hardness and impact test was used to evaluate the mechanical properties. Tafel test was applied to evaluate the corrosion behavior of base metal and weldments and the corrosion resitance and also the effect of heat input on that was examined. Corrosion test was conducted in 1M NaCl solution. The results showed that the amount of ferrite phase decreased from 59.4 to 49.4 as the heat input increses. Also only ferrie and austenite phases were observed in the microstructure without any other detrimental phases. The hardness test results showed that the hardness of weld metal went up in comparison with base metal. Furthermore, the more heat input was used, the more austenite phase was formed, the less weldment hardness was appeared. The impact test showed that the toughness of samples and the amount of austenite phase increases with heat input and subsequently the highest heat input welded sample showed the highest toughness and the lowest hardness. Tafel test showed that base metal has better corrosion behavior irrespective of the heat input of weldments. With the increasing of heat inpute the ferrite and austenite ratio approaches to 50/50 portion and the corrosion behavior improves. So the highest heat input welded sample, the better corrosion behavior. Eventually it can be said that whethere in terms of microstructure or mechanical properties included hardness and impact behavior or corrosion resistance the sample wich was welded with the highest heat input which is 1.87 Kj/mm, showed the best properties. Keywords : Tungsten- Arc welding method, Super duplex stainless steel, Heat-input, microstructure, mechanical properties, corrosion behavior.