Personal protective textiles (PPTs) protect humans from sharp objects. However, PPTs are designed primarily for protective performance, and their stiff material and single function make them unsuitable for long-term wear. In this study, we developed flexible protective textiles using advanced flat knitting technology. These textiles offer excellent cut resistance, good abrasion resistance, high flexibility, and warmth-retention properties. A flexible protective fabric (FPF) with knitted structure was designed with an outer layer that provides cut and abrasion resistance, an intermediate layer, and an inner layer for heat storage. The study examined the cut resistance, abrasion resistance, flexibility, thermal management, breathability and stability of the developed fabrics. FPF has excellent abrasion and cut resistance. The cut resistance of the fabric was tested in three directions. The warp cutting load was 2145 gf, while the weft cutting load was 2347 gf. The diagonal cutting load was the largest at 2364 gf, resulting in an A5 cutting grade for high cutting hazards. Compared with other protective fabrics available on the market, FPF stands out due to its softness and the smallest bending stiffness in both the warp and weft directions. Additionally, it has excellent thermal management performance and breathability, providing 53% insulation and 146 mm/s breathability. Stability tests have shown that FPF has excellent color fastness to perspiration, good cleaning stability and aging stability for cut resistance, flexibility, warmth-retention properties and breathability.