| Let F be a family of holomorphic functions in the plain domain D , k is a positive integer, a1(z) and a2(z) are two holomorphic functions in the plain domain D , and |a1(z)|2 + |a2(z)|2≠0 . If for every f(z)∈F, the zeros of f(z) are of multiplicity at least k , f(z)=0(?)|f(k)|≤M, (constant M≥0) and f(z)=ai(z)(?)f(k)=ai(z), i=1,2. then F is normal in D.Let F be a family of holomorphic functions in the plane domain D, k is a positive integer and k≥2.All of whose zeros have multiplicity of k , and satisfying the conditionf(z)=0(?)|f(k)(z)|<|z|,f(k)(z)≠z,Then F is normal in D. |