MOSFETs　offer　a　number　of　benefits　relative　to　traditional　power　devices.　These　include　a　higher　switching　frequency,　higher　operating　temperature,　and　higher　breakdown　voltage.　As　a　result,　there　has　been　considerable　interest　in　these　devices　within　the　industry.　However,　alongside　this　interest,　it　has　become　clear　that　the　reliability　of　MOSFETs　is　becoming　increasingly　significant　in　the　research　domain.　This　is　because　MOSFETs　are　used　in　a　wide　variety　of　applications　in　a　range　of　different　fields.　One　of　the　most　significant　causes　of　failure　in　MOSFET　modules　is　solder　layer　degradation,　which　encompasses　solder　layer　delamination　and　voids.　This　paper　therefore　investigates　the　impact　of　solder　layer　voids　on　the　electrical　and　thermal　characteristics　of　MOSFET　modules.　Firstly,　a　simplified　finite　element　model　is　established,　and　an　electro-thermal　simulation　analysis　is　carried　out　under　power　cycle　conditions.　Secondly,　finite　element　models　of　different　defective　solder　layers　are　established.　The　results　of　the　simulations　conducted　using　the　aforementioned　models　are　then　compared　and　analyzed.　The　analysis　reveals　that　the　temperature　on　the　chip　rises　in　direct　proportion　to　the　increase　in　defect　area,　while　the　current　density　of　the　solder　layer　also　increases　significantly　with　the　expansion　of　void　area.　This　provides　a　certain　reference　point　for　the　subsequent　study　of　solder　degradation.