The　macro　properties　of　fiber　reinforced　concrete　is　significantly　associated　with　the　spatial　distribution　of　fiber.　In　this　paper,　the　statistics-based　algorithms　characterizing　fiber　spatial　distribution　including　orientation　probability,　spacing　distance　and　wall　effect　were　proposed　based　on　the　established　the　random　generation　model　of　cylindrical　fibers　in　an　ideal　three-dimensional　fiber　reinforced　concrete　matrix.　The　influence　of　fiber　physical　parameters　on　the　overall　fiber　spatial　distribution　were　statistically　analyzed.　The　results　show　that　the　fiber　orientation　probability　in　ideal　fiber　reinforced　concrete　matrix　is　almost　constant.　The　fiber　geometric　size　plays　an　important　role　on　the　fiber　spatial　morphological　characteristics,　where　the　fiber　spacing　distance　increases　with　the　fiber　length　and　diameter,　and　the　wall　effect　is　significantly　affected　by　the　fiber　length.　The　heterogeneity　of　fiber　distribution　characterized　by　the　higher　fiber　spacing　distance　in　the　edge　region　is　associated　with　the　fiber　sparsity　mainly　influenced　by　the　single　fiber　volume　and　total　fiber　fraction.　With　the　constraints　of　wall　effect　and　principal　stress　direction,　the　boundary　region　parallel　to　the　principal　stress　has　a　higher　fiber　orientation　coefficient,　while　the　region　perpendicular　to　principle　stress　possesses　of　the　lowest　coefficient.　©　2023　Elsevier　Ltd