Abstract: The physical indexes and chemical constituents of microwave expanded bar-shaped stem shreds were determined and analyzed, and the effects of its application into cigarette were evaluated. The results showed that: 1) The filling value of microwave expanded bar-shaped stem shreds was similar to that of cut stem, though its size was smaller, its size distribution was more uniform. 2) The contents of total sugar and reducing sugar were higher in microwave expanded bar-shaped stem shreds. 3) With the increase of blending proportion of microwave expanded bar-shaped stem shreds, the individual weight, puff number and hot collapse of cigarette and the deliveries of tar, nicotine and CO in mainstream cigarette smoke decreased; while the draw resistance, tobacco loss from cigarette end, dust content and free combustion rate of cigarette increased; and the ash integration of cigarette improved. 4) At the same blending proportion, comparing with cut stem, the cigarette containing microwave expanded bar-shaped stem shreds showed higher individual weight, draw resistance, hardness, tobacco loss from cigarette end and dust content; lower standard deviation of individual weight and higher standard deviation of draw resistance; lower puff number and lower deliveries of tar, nicotine and CO in mainstream smoke; faster free combustion rate; smaller hot collapse and better ash integration, and significantly improved sensory quality.