The present work was aimed at in-situ studies of temperature and time induced phase transition, morphologic evolution, growth mechanism, and microstructure of KTi₆O₁₃ nano-whiskers synthesized by calcination reaction using nanometer TiO₂ as the starting material. The experimental results indicate that the use of nanometer TiO greatly reduces calcination temperature with a suitable calcination temperature range of 900~1100℃. Observation of morphologic evolution and dynamic HTXRD analysis show that the phase transition and growth of KTi₆O₁₃ whiskers are quite sensitive to calcination temperature, and the morphologic evolution of KTi₆O₁₃ whiskers is mainly based on the fulminous phase transition at the initial stage and subsequent concatenation-parallel growth in length and diameter. The growth of KTi₆O₁₃ whiskers follows the concatenation-parallel growth mechansim developed in this study, which directly results in the formation of growth steps along the axis of the whiskers.