Abs tractPseudothrombocytopenia (PTCP) can be an analytical error in the automatic blood cell count. Blood samples containing autoantibodies against platelets collected in ethylenediaminetetraacetic acid (EDTA) tubes can lead to platelet accumulation at room temperature. Agglutinated platelets are detected as larger cells using automated counters, which incorrectly leads to falsely low results. Hence, when a low platelet count is noted, PTCP must also be considered. In this study, we report a case of EDTA-dependent PTCP in a patient who has Hashimoto's thyroiditis with the current literature review.