Abstract:The species diversity indices and the species abundance distribution of Ouercus ilex L. woods in Veneto, Italy were studied. The results are as follows: 1. The Menhinicht s index, Shannont s index, Brillouin’s index, Simpsont s index Piulout s evenness, V′ evenness of PIE, V evenness of PIE, Mclntosh evenness could be used to study the diversity of O. ilex woods in Veneto. They showed that from the area of Lago ki Garda, to Foci del Tagliamento, Bosco Nordio, and Colli Euganei, the value of species diversity indices decreased gadually. 2. The geometric series of species abundance distribution dould be used best to study the diversity of O. ilex woods, and the log-normal distribution of species abundance distribution could also be a good index used to study did. The results of the study of species abundance distribution were the same as those of species diversity indices. 3. Diversity did not always increase in succession. In the earlier stage of succession, the diversity usually was relatively large owing to the invasion of many species and the lack of dominance. In the subsequent stage, the diversity was relatively minimized as the dominance increases. In the late stage, the diversity would increase as the structure of community became complicated and the number of species increased.