The　base　force　element　method　(BFEM),　formulated　according　the　principle　of　complementary　energy,　is　a　new　finite　element　method　(FEM)　that　deals　with　nonlinear　problems.　Using　the　BFEM,　the　linear　elastic　model　and　large　elastic　deformation　model　of　the　plane　truss　element　are　derived,　and　the　large　elastic　deformation　model　is　expanded　into　a　three-dimensional　setting　in　this　study.　The　rotating　part　of　the　element　should　be　considered　when　deriving　the　large　elastic　deformation　model.　Accordingly,　it　is　necessary　to　determine　whether　base　force　can　be　used　as　a　fundamental　unknown　variable.　Nonlinear　numerical　calculation　is　performed　in　combination　with　large　elastic　deformations　of　the　truss　beam　and　frame.　The　calculated　results　conform　with　the　theoretical　results　of　a　solid　beam　with　equivalent　deflection.　In　this　study,　the　U.L　and　T.L　formats　are　used　to　solve　the　governing　equations　iteratively.　The　calculated　results　in　the　T.L　format　are　compared　with　those　of　the　T2D2　and　LINK1　elements　in　the　finite　element　software.　Only　a　single　loading　of　the　T.L　format　is　necessary,　rendering　it　a　simple　and　convenient　approach　that　can　improve　calculation　efficiency.　Moreover,　the　arc-length　method　is　first　applied　to　the　BFEM　to　solve　the　snap-through　problem.