Precracked compact tension specimens of AISI type 304 stainless steel were tested for SCC in acidified NaCl solution at 381 K under conditions of increasing stress intensity factor. Crack growth rates were measured for the specimens in solution annealed, sensitised and 10% cold worked conditions. Acoustic emissions during crack growth were recorded in the stress intensity region where the influence of mechanical factors reaches a plateau and the crack growth is controlled by the environmental factors. For sensing the signals a piezo-electric sensor with a resonant frequency of 175 kHz was used. The gain was set at 80 dB and threshold at 1.5 V to offset the background noise of the boiling environment. the discontinuous nature of the acoustic signals showed that the crack propagation is by intermittent bursts. From the number of events per unit time and measured crack growth rates, it was estimated that the crack growth per event varied from less than a micron for solution annealed material to 15 microns for 10% cold worked material. Presence of crack arrest marks on the fracture surfaces also showed that the crack propagation was discontinuous. Diffusivity calculations showed that hydrogen generated at the crack tip due to corrosion reaction can diffuse much deeper than the crack increment per event. These observations and the measured activation energy for the crack growth process, which correspond to diffusion of hydrogen in austenitic stainless steels, showed that hydrogen plays a significant role in the cracking process. Probably, hydrogen produced in the corrosion reaction interacts with the plastically deformed zone at the crack tip causing microcleavage which gives discontinuous acoustic signals.