Poorly differentiated thyroid carcinoma (PDTC) and anaplastic thyroid carcinoma (ATC) are rare, aggressive thyroid cancers with poor prognosis. At present, there are a limited number of research reports on PDTC and ATC. The study aimed to analysis the predictive value of hematologic parameters and clinicopathological features of PDTC and ATC. This study retrospectively analyzed 67 patients at Tianjin Medical University Cancer Hospital from 2007 to 2019. We analyzed the clinicopathological features and survival outcomes of PDTC and ATC. This study showed that positive D-dimer, a high NLR, and a high PLR were more common in death patients. At the end of follow-up, 22 (32.8%) patients were alive at the time of study and 45 (67.2%) patients died from thyroid carcinoma. Disease-related death rates were 93.8% in ATC and 42.9% in the PDTC group. The median overall survival (OS) was 2.5 (0.3-84) months for patients with ATC, and 56 (3-113) months of PDTC patients. Univariate analysis showed that age at diagnosis and surgery were associations with OS in ATC patients, what's more, age at diagnosis, a high NLR, a high PLR, and positive D-dimer were associations with OS in PDTC patients. Multivariate analysis revealed that age at diagnosis was an independent association with OS in ATC patients. The hematologic parameters and clinicopathological features may provide predictive value of prognosis for patients with PTDC and ATC.