In this article, we study the fourth-order problem with the first and second derivatives in nonlinearity under nonlocal boundary value conditions2, 3). This equation describes the deflection of an elastic beam. Some inequality conditions on nonlinearity f are presented that guarantee the existence of positive solutions to the problem by the theory of fixed point index on a special cone in C 2 [0, 1]. Two examples are provided to support the main results under mixed boundary conditions involving multi-point with sign-changing coefficients and integral with sign-changing kernel. MSC: Primary 34B18; 34B10; secondary 34B15 Keywords: Positive solution; Fixed point index; Cone where β i [u] = 1 0 u(t) dB i (t) is Stieltjes integral with B i of bounded variation (i = 1, 2, 3). This equation describes the deflection of an elastic beam. Alves et al. [1] established the existence of positive solutions for the beam equationu (4) (t) = f t, u(t), u (t) under boundary conditions u(0) = u (0) = 0, u (1) = g u(1) , u (1) = 0 or u (1) = 0,