Abstract: Based on conformation analysis it has been found that the correlations among glas-sy transition temperature, Tg, cross-sectional area per chain, A, and steric factor ofinternal rotation, σ, for fluoropolymers are similar to those for other polymers. Theequation,Tg=973(σ-1.44), has been found for the estimation of the value of thesteric foctor of fluoropolymer chains. The fact that at the same values of steric factorthe glassy transition temperatures of fluoropolymers are higher than those of otherpolymers is attributed to the bensely packed chains of fluoropolymers.