A new generation of plant-based texturized meat analogues attempts to boost the consumption of dietary fiber. In the present study, oat fiber concentrate (OFC) and pea protein isolate (PPI) were combined (30:70; 50:50; 70:30) and processed with high-moisture extrusion (long cooling die temperature [LCDT]: 40, 60 and 80 °C; screw speed [SS]: 300, 400 and 500 rpm) to obtain meat-mimicking fibrous meat analogues (FMAs). The results showed that OFC reduced the structural strength (e.g., hardness, chewiness) of the FMAs, whereas LCDT strengthened the structure. Microtomography imaging revealed that FMAs containing more OFC presented smaller void thickness, thus reducing the FMAs' water holding capacity. An in-vitro gastrointestinal model showed that the extractability and viscosity of β-glucan were well preserved, particularly at low LCDT. Overall, it was possible to add substantial amounts of OFC (30–50%) to FMAs while maintaining fibrous meat-mimicking structures and retaining the oat fiber's viscous properties.