In the present article, the following nonlinear problem of new Hadamard fractional differential equations on an infinite interval H D ν x(t) + b(t)f (t, x(t)) + c(t) = 0, 1 < ν < 2, t ∈ (1, ∞), x(1) = 0, H D ν-1 x(∞) = m i=1 γ i H I β i x(η), is studied, where H D ν denotes the Hadamard fractional derivative of order ν, H I(•) is the Hadamard fractional integral, β i , γ i ≥ 0 (i = 1, 2,. .. , m), η ∈ (1, ∞) are constants and Γ (ν) > m i=1 γ i Γ (ν) Γ (ν + β i) (log η) ν+β i-1. By making use of a fixed point theorem for generalized concave operators, the existence and uniqueness of positive solutions is established. Moreover, an application of the established results is also presented via an interesting example.