There　are　many　uncertain　errors　during　the　A/D　and　the　D/A　processes,　and　also　in　the　fixed-point　calculation　when　proportional-integral-derivative　(PM)　controller　was　employed　in　the　engine　control　module.　These　will　cause　the　perturbations　of　the　parameters　of　PID　controller.　The　robust　stability　performance　of　PID　controller　should　be　taken　into　account.　It　must　be　guaranteed　that　the　uncertainties　of　the　coefficients　of　the　plant　and　the　controller　will　not　result　in　the　feedback　system　unstable.　The　PID　controller　for　the　boost　pressure　control　of　a　turbocharged　diesel　engine　was　designed　based　on　the　identified　third　order　plant　model.　The　parameters　stability　space　of　the　PID　controller　was　analyzed　according　to　Hurwitz　stability　criterion.　Using　nonlinear　programming　method,　the　radius　of　the　maximum　stability　ball　of　the　parameters　of　Kp,　Ki　and　Kd,　which　was　centered　at　the　tuned　values　calculated　according　to　ISTE　criterion,　was　computed.　The　permitted　maximum　uncertainty　of　the　coefficients　of　the　plant　model　denoted　by　the　infinite　norm　was　also　analyzed　based　on　the　Edge　Theorem.　The　results　indicate　that　the　tuned　PID　controller　has　good　time　domain　performance,　at　the　same　time,　the　robust　stability　could　satisfy　the　requirements.