This　paper　presents　a　dynamic　electro-thermal　model　for　the　V-　and　Z-shaped　electrothermal　microactuator　for　the　first　time.　The　model　predicts　the　dynamic　temperature　responses　of　the　actuator　operating　in　vacuum　conditions　with　constant　input　voltage　applied　at　both　ends.　Dynamics　of　the　temperature　distribution　are　established,　and　the　exact　solution　of　the　hybrid　partial　differential　equation　(PDE)　is　obtained　to　describe　the　electro-thermal　behavior　for　each　segment　of　the　actuator.　To　solve　the　PDE,　the　final　temperature　responses　are　intentionally　decomposed　into　two　parts,　i.e.,　the　steady-state　and　transient　responses.　In　addition　to　the　initial　and　boundary　conditions,　continuity　conditions　that　describe　the　temperature　and　heat　flux　density　between　adjacent　segments　of　the　actuator　are　employed　to　solve　the　hybrid　PDE.　The　validation　of　the　model　is　conducted　by　finite-element　simulations　using　ANSYS　software　(version　14.0).　The　analytical　results　based　on　the　proposed　model　well　agree　with　the　numerical　results　with　ANSYS　analysis　in　terms　of　predictions　on　both　steady-state　and　transient　responses.　Along　with　the　line-shaped　beam　model,　this　proposed　model　serves　as　the　first　sub-model　in　establishing　the　complete　dynamic　electro-thermal-mechanical　model　for　the　V-　and　Z-shaped　actuators.　The　developed　modeling　method　paves　the　way　in　improving　the　design　and　optimizing　the　dimensions　of　the　actuator　in　achieving　better　static　and　dynamic　performances.　©　2016　IEEE.