The Guizhong Depression in middle Guangxi province is a large Neopaleozoic marine sedimentary one that was developed on the base of Caledonian Movement and it has been evolved into a residual basin filled with Neopaleozoic and Triassic strata. The Devonian strata buried deeply are the main exploration targets. The drilled result demonstrates the existence of two suits of Devonian -Carboniferous source -reservoir -cap associations in WellGuizhong-1, in which three kinds of hydrocarbon showings were discovered, i.e. gas-testing abnormality, oil-traced sandstone and solid bitumen. The solid bitumen-showing intervals are thick up to 709m in Devonian strata. The hydrocarbon (bitumen) of paleo-reservoir mainly derives from middle-lower Devonian Tangding and Luofu mudstone in Guizhong Depression. The solid bitumen in Well Guizhong-1 and the paleo-reservoir at Dachang is pyrobitumen, one of the thermal cracking products of hydrocarbon. Two phases of hydrocarbon charging underwent in the trap ofGuizhong-1. The first was during the dominant one of hydrocarbon generation before Indo-Chinese Epoch, and the second (the late phase) was during Yanshan-Himalayan Epoch, which is represented by the dissoluble hydrocarbon nearby with the hydrocarbon showing interval. Three times of hydrocarbon reservoir reconstructions went through in this depression. During the first, the hydrocarbon that accumulated before Indo-Chinese Epoch underwent thermal cracking due to subsidence and was changed into solid bitumen and methane gas. During the second, the thermal alteration of hydrocarbon happened under higher temperature caused by Later Yanshan magmatic activity. During the third, the gas formed in the reservoirs due to Upper Devonian reservoir reconstruction or destruction caused by Himalayan Movement. The gas accumulated during late phase is the future direction of exploration. The western part of Guizhong Depression is an area favourable for gas accumulation and preservation owing to relatively integrated strata (so the exploration targets are buried deeply) and undeveloping faults and magma activities.