We prepared Bi2Sr2CaCu2Oz (Bi-2212) single crystals using the starting materials with the compositions of Bi2Sr2-xLaxCaCu2Oz (x = 0-0.3) and Bi2Sr2Ca1-xLayCu2Oz (y = 0-0.3) in a self-flux method, and investigated the characteristics of the single crystals. From the results, we found that the T, and the composition of the single crystals prepared using Bi2Sr2-xLaxCaCu2Oz were different from those prepared using Bi2Sr2Ca1-yLayCu2Oz. Therefore, probably there are two kinds of La-doped Bi-2212 single crystals, where La occupies Sr or Ca site. (C) 2002 Elsevier Science B.V. All rights reserved.