Traditional　multi-axle　steering　vehicle　often　adopts　linear　state　feedback　control,　which　is　difficult　to　ensure　high-precision　trajectory　tracking　under　all　working　conditions.　Moreover,　due　to　the　failure　to　consider　the　optimal　distribution　of　tire　lateral　and　longitudinal　forces,　tires　are　prone　to　problems　such　as　uneven　load　rates　and　wear.　In　this　paper,　considering　the　over-redundant　and　nonlinear　characteristics　of　three-axle　vehicle,　a　hierarchical　coordinated　control　strategy　is　proposed.　In　the　upper　layer,　the　trajectory　tracking　controller　is　designed　based　on　the　robust　nonlinear　sliding　mode　control　theory.　In　the　middle　layer,　based　on　the　optimization　conditions　of　tire　load　rate　and　dissipative　energy,　the　lateral　and　longitudinal　forces　optimal　distribution　controller　is　constructed　under　the　constraint　of　friction　circle.　In　the　lower　layer,　the　lateral　and　longitudinal　forces　are　finally　converted　into　tire　angles　and　torques　with　the　tire　inverse　model.　The　results　show　that　the　hierarchical　coordinated　control　strategy　can　ensure　that　the　multi-axle　vehicle　can　achieve　high-precision　trajectory　tracking　under　all-terrain　load　conditions,　and　the　load　rate　and　wear　of　each　tire　are　relatively　uniform.　The　coordinated　control　strategy　proposed　in　this　paper　considers　the　influence　of　nonlinear　characteristic　of　vehicle　and　tire　lateral　and　longitudinal　forces　distribution　on　steering　coordination,　which　can　provide　an　important　theoretical　basis　for　the　further　improvement　of　steering　coordination　of　multi-axle　vehicle.