A new automatic rotary compactor and its abilities in compacting stone mastic asphalt(SMA) are presented. Following an overview of the rotary compactor and the compaction procedure, it is demonstrated that the rotary compactor is able to produce uniform slabs with the desired thickness of 65 mm all over around. Furthermore, 132 cored samples from the rotary compactor had been compacted uniformly with approximately 4% optimum air void content. In addition, performance tests results indicate that the rotary compactor produces asphalt mixtures with the requirements of resilient modulus, Marshall stability and flow. A weight factor was introduced for each fraction of aggregates in the degradation analysis to compensate the crushing effect of aggregates during mixing and compacting. A new automatic rotary compactor and its abilities in compacting stone mastic asphalt (SMA) are presented. Following an overview of the rotary compactor and the compaction procedure, it is demonstrated that the rotary compactor is able to produce uniform slabs with the desired thickness of 65 In addition, the performance tests results indicate that the rotary compactor produces asphalt mixtures with the requirements of resilient modulus, Marshall stability and flow. A weight factor was introduced for each fraction of aggregates in the degradation analysis to compensate the crushing effect of aggregates during mixing and compacting.