Relationships among tiger-striped flow mark patterns appeared in injection moldings, molecular characteristics, especially molecular weight distribution of polypropylenes (PP) and rheological properties of PP/talc compounds have been investigated. Usual tiger-striped flow mark pattern observed on one side of injection moldings of PP/talc compounds shows alternately bright and dark areas in the direction of flow and the pattern on the other side reverses out-of-phase with brightness. But the flow mark patterns of some PP/talc compounds are quite different from the usual one. The patterns on both side of injection moldings are in-phase and/or change halfway from in-phase to out-of-phase. We speculated the different flow mark patterns appeared in the injection moldings would result from the different flow behaviors of flow front during the injection stage of injection molding process. We also found that the flow mark of PP/talc compounds composed of PP with wide molecular weight distribution was in-phase pattern. In this study we will discuss the relationship the flow behaviors of flow fronts and tiger-striped flow mark patterns of PP/talc compounds and also propose an improvement of tiger-striped flow mark of PP/talc compounds.