This paper considers a lower bound estimation over L-P (R-d) (1 <= p < infinity) risk for d dimensional regression functions in Besov spaces based on biased data. We provide the best possible lower bound up to a Inn factor by using wavelet methods. When the weight function w(x, y) equivalent to 1 and d = 1, our result reduces to Chesneau's theorem, see Chesneau (2007). (C) 2015 Elsevier B.V. All rights reserved.