Optical absorption, emission, and carrier recombination characteristics of Al(x)Ga(1-x)N epilayers (x = 0.17, 0.26, and 0.33) were systematically studied by means of transmission, photo luminescence (PL), and time-resolved PL spectroscopy, respectively, A typical energy-gap shrinkage behaviour with temperature was confirmed for all the Al(x)Ga(1-x)N epilayers by transmission measurements. However, we observed anomalous PL temperature dependences such as a decrease-increase-decrease behavior of the PL peak energy shift and an increase-decrease-increase behavior of the spectral width broadening with increasing temperature. The anomalous temperature-induced emission shift is attributed to energy tail states due to alloy potential inhomogeneities in the Al(x)Ga(1-x)N epilayers with large Al content.