This is a state-of-the-art overview of the critical features, varieties, and uses of nanocomposite fibres based on polyacrylonitrile. Polyacrylonitrile (PAN) is an economically important acrylic polymer with superior chemical, thermal, mechanical, and electrical properties. Membranes utilized in the biomedical fields can be used as implantable materials and bio-separative materials, with a role in regenerative and purification techniques. Out of all the techniques, electrospinning is given preference over other scaffold preparation methods because it can create 3D nanofiber structures. Electrospun nanofibers also have unique qualities, such as a high surface area-to-volume ratio, porosity, stability, permeability, and morphology that resembles an extracellular matrix. The introduction of nanofillers (carbon nanotubes, graphene oxides), and various nanocomposites into the electrospun PAN fibres. The nitrile groups' interfacial bonding with nanofillers has enhanced the properties of PAN nanofibers. The chemical structure, superhydrophobicity, superoleophobicity, porosity, and wettability of nanofibers have developed a variety of advantageous nanocomposites for fibre applications. The primary goal of the review is to update on the recent research PAN with various polymer blends and nanocomposites for biomedical applications. Furthermore, the implanted materials' biological treatments and therapeutic modalities and their advantages and disadvantages and developing processes are reviewed. Therefore, this review aims to present an in-depth investigation of PAN, its nanofiber composites, and their related features that make them appropriate for bioactive materials.