The Lannigou gold dePOsit is hosted in turbidite sequences of Middle Triassicfound in Southwest Guizhou, China, in which gold occurs as sub-micron and disseminated particles. The deposit was studied by many ways including organic petrology, organic geochemistry and gold test in kerogens in this paper.Total organic carbon content of whole rock in Lannigou ranges from 0.06% to1.18%, in which ores have slightly higher values than their host rocks. Kerogensseparated from both ores and hosts are all sapropelic-humic type (II2), and no apparent differeces are found. Comparing with the hosts, kerogens in the ores showhigher maturity(R0 =2.74 %-3.06% )and noticeably higher gold content (6.15-24.80μg/g), and the differences are larger than 0.14%--0.46% and 4.79-23.44μg/g, respectively. However, the ratios of total gold content of kerogens to whole rocksare apparently higher for hosts than for ores.Organic geochemical analysis shows that soluble organic compounds may be preserved in some rocks with high maturity due to mineral preservation for organicmatter. Examination of saturated and aromatic hydrocarbons separated from chloroform bitumen "A" demonstrated that organic matter in ores responses an environment characterized by high salinity and strong reducibility, and that much asphalteneand/or sulphur-bearing organic compound exists. In addition, dissimilar to ores,there are marked evidences of ocean biomarker compounds preserved in host samples.An integrated research shows that: (1) organisms of gold-hosted rocks, controlled by faults, were activated by both shearing and hydrothermal fluids in the faultzones, and thus became an excellent scarenger for small concentrations of dissolvedgold; (2) kerogen of humic type has much more aromatic nucleuses and is muchmore close to structure of activated carbon, so the Middle Triassic formation inLannigou is also suitable for concentration of sub-micro gold, though total contentof gold in the kerogen does not have industrial significance due to lower contentof organisms; (3) transportation and precipitation of gold may be to a large extentrelated to existence and destroy of unsaturated ligands, including aromatic and/orsulphur-bearing organic groups.