A model of spheroidal particles is used to calculate the steady-state temperature of dust grains immersed in the interstellar radiation field .
It is found that the temperature of non-spherical grains with the aspect ratios a / b \la 2 deviates from that of spheres less than 10 % .
More elongated or flattened particles are usually cooler than spheres of the same mass and in some cases the temperatures may differ by even about a factor of 2 .
The shape effects increase with the infrared absorptivity of the grain material and seem to be more important in dark interstellar clouds .