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A numerical simulation framework to address the problem of the interaction of moving and/or deformable slender object(s) within an incompressible fluid flow is proposed. In this work, the finite element method (FEM) for structural dynamics simulation is introduced in immersed boundary-lattice Boltzmann method (IB-LBM). The variant immersed boundary-lattice Boltzmann method proposed by Shu et al.is referred, which satisfies the non-slip boundary condition well at the boundary point. In this framework, the fluid and solid domains are both encompassed by Cartesian uniform lattices. The deforming/moving objects are divided into several elements, which nodes are set as Lagrangian markers to track the boundary of structure in immersed boundary method. At each simulation step, by using the law of conservation of momentum at each Lagrangian boundary point, the loads acting on the structure in IB-LBM are obtained first. Then, the loads are used in structural kinetic equations to calculate the displacement and velocity of Lagrangian boundary point, which will be brought back into IB-LBM for the next iteration. Compared to other lattice Boltzmann–immersed boundary method proposed, which can only solve the specific fluid-structure interaction problems, the framework proposed in this article is more general because of its strong modeling capability by introducing FEM. Here, nonlinear FEM solver was developed to account for ;geometrical and material non-linearity of flexible objects. Four cases were used to validate capability of this framework. In the first case, we consider the laminar incompressible channel flow around a flexible filament clamped behind a rigid stationary cylinder which results in self-induced oscillations of the structure. The results agree very well with available data in the literature. The beating of tandem filaments induced by the fluid-structure interaction was investigated. Then, the interaction mechanism was compared by changing Reynolds number, elasticity modulus and density of the filament. In the third and fourth case, two identical objects used in first case were located in flow with one arranged side by side, and another in a line. For the last two cases, the influence of the distance between each object on the flow field was analyzed.