4-point　dynamic　bending　tests　of　board　level　electronics　packages　were　carried　out　in　order　to　investigate　the　reliability　of　solder　joints.　A　high　speed　camera　and　the　digital　image　correlation　method　were　used　to　measure　the　deflection　of　the　PCB　board.　A　finite　element　model　to　simulate　the　test　was　built　up　and　was　validated　by　the　test　data.　A　parameter　study　was　subsequently　implemented.　The　results　show　that　at　certain　value　of　PCB　stiffness　the　peeling　stress　reaches　its　peak.　The　package　installation　angel　has　significant　effect　on　the　peeling　stress　of　the　solder　joints.