The invention provides a fully-mechanized sublevel caving face section-free coal pillar mining method for thick coal layer. The method comprises the following steps: in a thick coal layer, mining is carried out according to a multi-section sequence, wherein the position of a first mining section is higher than that of a second mining section; a ventilation roadway of the current mining section is distributed just above a transportation roadway of the former mining section along a roof of the coal layer; and a transportation roadway of the current mining section is distributed along a bottom plate of the coal layer. With the adoption of the method provided by the invention, the possibility of impact ground pressure on the bottom plate is effectively reduced, so that the dangers that bottom coal is flushed out of the bottom plate and the roadway is blocked are reduced, and the mining safety is improved.