There have been many applications of confluent hypergeometric functions in quantum mechanics and statistics. Furthermore, many problems in mathematical physics can be solved with the help of the location of zeros of confluent hypergeometric functions. In this paper, we study the zero sets of the confluent hypergeometric function 1F1(α;γ;z):=zn, where α,γ,γ-α∉Z ≤ 0, and show that if {zn}n=1∞ is the zero set of F(α;γ;z) with multiple zeros repeated and modulus in increasing order, then there exists a constant M > 0 such that|zn|≥ Mn for all n ≥ 1.