Bistable　composite　structures　have　attracted　growing　interest　in　morphing　applications　to　aerospace　industry.　Here,　we　device　a　novel　prestrained　bistable　composite　gridded　structure,　consisting　pairs　of　prestrained　composite　strips　on　both　sides　and　oriented　in　90°.　This　is　achieved　by　employing　the　elastic　fibre　prestressing　(EFP)　technique,　where　a　plain-weave　carbon　prepreg　was　stretched　in　two　directions　at　a　constant　strain　level,　and　the　tensile　strain　was　maintained　throughout　the　curing　process　to　produce　a　prestrained　composite　trip.　Upon　load　removal,　recovery　from　the　prestrained　carbon　fibres　generates　compressive　stresses　and　interacts　with　thermal　residual　stresses,　which　in　turn　changing　the　in-plane　stress　level　within　a　composite　structure　and　induce　out-of-plane　deflections.　Therefore,　the　bistability　is　generated　from　the　pairs　of　the　oriented　prestrained　composite　strips,　their　deflections　give　opposite　cylindrical　configurations　to　the　mid-plane.　Here,　we　presented　further　details　on　the　biaxial　fibre　straining　rig;　samples　were　produced　with　different　prestrain　levels,　in　order　to　reveal　the　underlying　mechanisms　from　the　fibre　prestraining.　These　results　provide　valuable　insights　for　the　design　of　aerospace　deployable　structures.　©　The　Author(s),　under　exclusive　license　to　Springer　Nature　Singapore　Pte　Ltd.　2024.