One of the common problems in the medical parasitology laboratory is the differentiation of parasites from other elements in the stool and body fluids so-called "artifacts". Artifacts generally referred to living or abiotic agents that embedded in the clinical sample and may misleading the lab because of their similarity to parasitic organisms. Artifacts are an integral part of the diagnosis process and they are cause of common misdiagnosis in the laboratory. Their differentiation from pathogenic parasitic agents is done by proper diagnosis, which leads to proper treatment of parasitic infections. As usually an inexperienced technician often misdiagnosed a yeast or other plant cell as amoeba or considers a platelet as a malaria parasite, it may be unsuccessful to identify parasitic organisms that really exist in the stool sample. The major forms that cause confusion and misdiagnosis in parasitology laboratory are spores, fat droplets, yeast, red blood cells, and macrophages. Compared with other parts of the medical laboratory, in parasitology lab less attention observe to this problem. The consequence is the reporting of false positive results, incorrect treatment, and patient injury. Identifying, introducing, and differentiating artifacts for laboratory personnel, especially inexperienced, are an important factor in accurate diagnosis. In the present study, key diagnostic points of parasitic organisms and artifacts have been categories.