In this study, corrosion behaviour of 304L austenitic stainless steel, which was obtained from boiler pipe at sugar plant and its weldment samples, which were produced with gas tungsten arc welding (GTAW) technique at varied ranges of GTAW current were investigated in demineralised water - being the operating environment of the boiler. Potentiodynamic polarization measurement was conducted on the samples. And the pitting corrosion attack that was developed on the samples’ surfaces at the varied ranges of GTAW current was analysed by Optical microscopy. The results revealed that microstructures of the weldment samples after corrosion at 25oC were characterised by pits of varying sizes and alignment. Inclusions, precipitates and δ ferrite were observed within the microstructures. With increasing and decreasing GTAW speed, values of Ecorr icorr and βa were shifted to less negative direction (more nobility) and more negative (less nobility) direction respectively. Optimum and least Ecorr values of 3.2253x10-1V Ag/AgCl and 1.7327x10-1V Ag/AgCl were obtained at GTAW speed of 5.4mm/s and at 1.7 mm/s respectively.