Objectives: Although carbonates related to methane seepage seep were widely reported in modern sediment or sedimentary rocks (especially since Carboniferous), researches about cold seep carbonates associated with sedimentary deposits were rarely reported. In the study, we report the nodular limestone linked to the leakage of methane and other hydrocarbons, which was newly found in Xiyahe Devonian barite deposit, Guizhou Province. Methods: A detailed field survey was conducted on Xiyahe Devonian barite deposits. 9 samples of nodular limestone in the research were collected from Xiyahe section. In order to observe micro characteristics of the nodular limestones, 9 limestone samples were observed by Polarization microscope in College of Resources and Environmental Engineering, Guizhou University and scan electron microscope in State Key Laboratory of Ore Deposit Geochemistry Chinese Academy Science, Guizhou, China. The limestones were ground to less than 200 mesh for the use of X-Ray Diffraction (XRD), major element, stable carbon, oxygen isotope and rare earth element (REE) analyses. REE analyses were carried out in State Key Laboratory of Ore Deposit Geochemistry Chinese Academy Science, with ELAN DRC-e Q - ICP - MS made in Canada PerkinElmer. The major elements were measured with ME-XRF26d in ALS Minerals-ALS Chemex. Carbon and oxygen isotope analyses were carried out in the Key National Laboratory of Environmental Geochemistry of the Institute of Geochemistry under the Chinese Academy of Sciences. The instrument used was a gas-stable isotope mass spectrometer, which type is MAT253. The end results were corrected by carbonate rock solid standard. All analysis results were compared with the V-PDB standard. The precisions for δ13Cand δ18O are better than ±0.05‰ and ±0.08‰ respectively. Results: Carbonate clots and framboidal pyrites were found in the nodular limestones. The interior texture present sunflower shape in framboidal pyrites, single pyrite have clear outline and similar size. The δ13CV-PDB values of limestones in Xiyahe vary from -10.27‰ to +3.736，average value is -3.18‰; Xiyahe nodular limestone have relatively light oxygen isotope compositions with δ18OVPDB values ranging from -8.20‰ to -2.26‰，average value is -6.04‰. The minvalue of δ13CVPDB of limestone is -10.27‰. The total REE contents of 9 limestone samples in Xiyahe section range from 2.62×10-6 to 43.49×10-6, average value is 21.9×10-6. Ce/Ce* values vary from 0.50×10-6 to 0.78×10-6, but the revised results following Bau and Dulski’s method (Bau et al. 1996 ) indicate real Ce anomaly occurrence in six samples, the others are not real Ce anomaly. Moreover, the major elements of limestone are mainly CaO and SiO2.  Conclusions: Amounts of nodular limestones were found in Xiyahe barite deposit. And the shape of nodular limestones are spherical, elliptic spherical and tubular. The micro characteristics of nodular limestone are similar to modern cold seep carbonate (such as; carbonate clot, framboidal pyrite), and its carbon isotopes contents are also similar to modern carbonate associated with the leckage of methane. These results indicate the genesis of the nodular limestones in Xiyahe Devonian barite deposits was related to the leakage of methane and other hydrocarbons, but the petrographic observations of limestones and earlier studies on Xiyahe barite deposit suggest pyrolytic methane is the dominant carbon source of the limestone in Xiyahe barite deposit. The Ce anomaly of limestones show not only deoxidation in ancient sedimentary environment, but also intermittent oxidation are reflected. The situation may be affected by methane fluid leakage rate.