Surface characteristics and morphology, specially surface roughness of dental amalgam, can influence the surface plaque accumulation, gingival inflammation, recurrence of tooth caries, tarnish and corrosion behavior of the alloy. This study was designed to evaluate the effect of the particle shape of amalgam alloy on the surface morphology and roughness of amalgams in addition to this effect from carving, burnishing and polishing.Four types of commercial amalgam alloys with different particle shapes were used for this investigation including lathe cut, spherical, spheroidal. Twenty one samples were prepared from each amalgam in special mold. Following aninitial trituration and condensation; samples of each amalgam alloy were divided into three groups and each group was finished and polished using one of three following procedures; carving, carving - burnishing, carving - burnishing polishing. SEM Technique was used to investigate the surface morphology of amalgams. The mean values were statistically compared using ANOV A and Duncan tests at 95% level of confidence.Results showed a statistically significant difference between three different groups of each amalgam in their surface roughness (p<0.05). The mean surface roughnesses of the" carved four amalgam types indicated a significant difference between groups (P<0.05). However, the carved - burnished groups and carved burnished - polished groups had no significant difference (P>0.05).It seems that the shape of the particle has a clear effect on the surface roughness, however, a good finishing and polishing could usually compensate this effect.