The　turning　load　resistance　torque　of　large　wheeled　vehicles　is　very　big　and　these　vehicles　are　all　the　multi-axle　vehicles.　It　is　important　to　select　the　suitable　steering　system.　In　the　multi-axle　vehicle　steering　system,　EHPS　is　the　most　appreciate　driving　mode　in　all　of　them　including　MS,　HPS,　EHPS,　EPS,　etc.　In　order　to　improve　the　performance　of　the　present　EHPS　with　proportional　valve,　the　new　EHPS　with　servo　solenoid　valve　was　designed.　The　static　and　dynamic　characteristics　of　servo　solenoid　valve　are　much　better　than　proportional　valve,　such　as　dead　band,　hysteresis　and　frequency　response.　Firstly,　the　single-axle　electro-hydraulic　servo　steering　system　was　introduced　including　hydraulic　system　and　electronic　control　system.　Then　multi-axle　electro-hydraulic　servo　steering　system　with　coordination　control　strategy　was　introduced.　The　designed　multi-axle　steering　system　with　servo　solenoid　valve　makes　it　possible　to　improve　the　steering　performance　significantly.　©　(2013)　Trans　Tech　Publications,　Switzerland.