Dysfibrinogenemia is characterized by the presence of functional abnormalities despite the maintenance of normal levels of fibrinogen antigen. Plasma fibrinogen level is commonly measured by Clauss fibrinogen assay (CFA).Although CFA may underestimate the true antigen level in patients with dysfibrinogenemia, the clot waveform helps distinguish between true low fibrinogen values and those caused by qualitative abnormalities. Case 1 was a woman in her 50s with persistent proteinuria and no history of bleeding disorders who showed a low fibrinogen level before renal biopsy. Based on the CFA clot waveform, dysfibrinogenemia was diagnosed. The renal biopsy was performed without significant bleeding complications, and replacement therapy was not required. Case 2 was a pregnant woman in her 30s with no history of bleeding disorders who showed a low fibrinogen level prior to her second childbirth. The CFA clot waveform indicated a preserved antigen level, leading to a diagnosis of dysfibrinogenemia. She had a successful delivery without any replacement therapy. In both cases, the presence of a heterozygous missense mutation in the fibrinogen γ chain (γArg301His) was confirmed. The CFA clot waveform is useful in diagnosing dysfibrinogenemia and determining treatment strategies in patients with low levels of fibrinogen without bleeding symptoms.