(1) modes of expression of thermosensitivity and theoretical interpretation of thermal dose, (2) differential thermosensitivities between strains of cells and the possible correlation to heat shock proteins and their syntheses, (3) cell phase responses to hyperthermia, (4) low hyperthermia and the induction of thermotolerance, (5) comparative thermosensitivities at the temperatures between below and above 42.5 degrees C -43 degrees C, (6) Arrhenius plot and mean cellular lethal heating periods, (7) step-up heating and the thermotolerance induction, (8) step-down heating and the thermoenhancement, (9) fractionated high hyperthermia and the thermotolerance induction and (10) modification of thermosensitivity by chemical substance including anticancer drugs; are compactly reviewed mainly on cell level.