Abstract: Fixed-bed reactors are of great advantage in decreasing the volume necessary for thermochemical energy storage. The radial and tangential temperature distributions in fixed beds are experimentally investigated. The experimental results reveal that there is a prominent "hump" in the radial temperature profile near the wall region. Comparison of the radial temperature profiles under different conditions indicates that the location of the "humps" in radial temperature profiles has no relation with both the Renolds number and the bed length. The abrupt change in the temperature profile is completely determined by the inhomogeneous bed structure resulting from the radial voidage distribution near the wall region of the fixed-bed tube. The tangential temperature distribution does not show any explicit relations with the tangential location. Its perturbation along the tangential direction can be ascribed to the random distribution characteristics caused by the randomness of the catalyst particles packed in the bed.