The rheological behaviour of two different molecular weights of a thermotropic liquid crystalline cellulose derivative, acetoxypropylcellulose (APC), at T = 120 degrees C, has already been reported [1]. In this work we present the temperature dependence of the rheological properties of two molecular weights of APC. The shear viscosity, eta, and first normal stress difference, N-1, were measured at temperatures T = 120, 130 and 140 degrees C, for (M) over bar(W) = 94000g/mole, and T = 120 and 140 degrees C for (M) over bar(W) = 129000 g/mole, and for shear rates, (gamma) over dot, between 0.01 and 10 s(-1). The shear viscosity eta((gamma) over dot) decreases with increasing T, for both samples, showing a strong shear thinning behaviour at all temperatures and over the whole range of (gamma) over dot studied, except for shear rates between about 0.2 and 1 s(-1) (depending on Mw and T), where a quasi-Newtonian plateau is observed. The first normal stress difference N-1((gamma) over dot) also decreases with increasing T at a given (gamma) over dot. It increases with shear rate over the whole (gamma) over dot range studied, and shows an inflection at (gamma) over dot values slightly above (gamma) over dot = 1/tau, where tau is the relaxation time of the polymer memory function. The temperature dependence of the shear viscosity was fitted to an Arrhenius law, giving an apparent activation energy (E-a) in the order of 8-15 kcal/mole, depending on molecular weight and shear rate. The activation energy was found to increase with molecular weight (at a given (gamma) over dot). The variation of E-a with (gamma) over dot, for (M) over bar(W) = 94000 g/mole, shows a minimum at (gamma) over dot approximate to 2 s(-1) Using a continuum theory for nematic polymers. proposed by Martins [2], some fundamental parameters were obtained from the fit of the theory to the experimental data. Using these parameters it was possible to construct a "master curve" for the viscosity, eta((gamma) over dot), in good agreement with the experimental data.