A new oscillation criterion for a class of higher order nonlinear differential equation x^(n)(t)+p(t)f(x(t),x(t1(t)),x(r2(t)),…,x(rm(t)))g(x^(n-1)(t))=0was investigated, where n is an even positive integer, p∈C([t0,+∞],R0),f∈C(Rm+1,R),g∈C(R,R),g〉0 and for every ui〉0(i=1,…,m+1), f(u1,…,um+1)〉0, for every uui〈0(i=1,…,m+1),f(u1,…,um+1)〈0.