In this paper, we consider identifying codes in binary Hamming spaces F n , i.e., in binary hypercubes. The concept of (r, )-identifying codes was introduced by Karpovsky, Chakrabarty and Levitin in 1998. Currently, the subject forms a topic of its own with several possible applications, for example, to sensor networks. Let us denote by M ( ) r (n) the smallest possible cardinality of an (r, )-identifying code in F n . In 2002, Honkala and Lobstein showed for = 1 that lim n→∞ 1 n log 2 M ( ) r (n) = 1 − h(ρ),where r = ρn , ρ ∈ [0, 1) and h(x) is the binary entropy function. In this paper, we prove that this result holds for any fixed 1 when ρ ∈ [0, 1/2). We also show that M ( )for every fixed and r slightly less than n/2, and give an explicit construction of small (r, 2)-identifying codes for r = n/2 − 1.