Abstract: It is reviewed in this article the progress of petroleum geochemistry in hydrocarbon generation,migration and accumulation,including: discerning technology of hydrocarbon precursors using biomarkers and carbon number distribution of alkanes,as well as the isotopic composition of alkanes;whether source rock is coal bed or mudstone in coal sequence,carbonate or mudstone in carbonate sequence;significance of amber in the Middle East oil fields;determination of maturity with FAMM technology and ring number distribution of aromatic hydrocarbons;catalytic hydrocracking technology of asphaltene and pyrobitumen for discerning their precursors;oil preservation in deep buried horizons within closed system;Proterozoic petroleum prospect in China,especially in the Ordos Basin;new idea for thermal simulation experiment of hydrocarbon generation;determination of time,temperature and pressure circumstance of petroleum migration and accumulation;possible mechanism of migration and accumulation of immature oils;simulation experiment of petroleum migration and accumulation;moving-ahead markers and lagging-behind markers for petroleum migration;and at last difficulties of petroleum geochemistry exploration on earth surface,i.e.the technology for enhancing signal versus noise ratio and reconstructing heavily tortured surface projection.