The　effects　of　pre-loading　on　the　dynamic　behaviour　of　concrete　were　experimentally　investigated　in　a　series　of　split　Hopkinson　pressure　bar　tests.　Cylindrical　specimens　with　three　water/cement　ratios　and　two　kinds　of　aggregates　were　tested.　The　effects　of　pre-loading　and　strain　rates　on　the　dynamic　stress-strain　relationship,　strength,　energy　absorption　capability　and　failure　modes　were　investigated.　The　results　showed　that　when　the　pre-loading　was　smaller　than　30%　of　the　static　compressive　strength,　its　effect　on　dynamic　strength　could　be　ignored.　However,　a　29%　reduction　in　dynamic　strength　was　observed　when　the　pre-loading　was　higher　than　40%　of　the　static　strength.　In　addition,　the　pre-loaded　specimens　exhibited　greater　strain-rate　dependence.　An　empirical　model　considering　the　effects　of　pre-loading　and　strain　rate　was　developed　based　on　the　test　data.