The high dense pure cordierite ceramics and liquid-phase-sintering cordierite ceramics were prepared with the starting powder made by sol-gel progress. The porosities of them are less than 6.21%, and some can be up to 1.0% especially. The flexural strength of the sample can get to 167 MPa, which is greater than that of 103 MPa of pure cordierite ceramics. The composition, fracture behavior and microstructure of the liquid-phase-sintering cordierite ceramics are investigated. The result shows that the increased flexural strength is mainly attributed to the change in cell parameters of cordierite and the small grain size.