Yes, he will. However, he will just start back at his previous save spot.
Edit by Crypt19: Well, in universe, it's inevitable that he will die, unless "G-man" or someone similar (Vortigaunts maybe?) grant him immortality. Also, the (apparently)non-canon (part of the official story) alternate ending to Half-Life, he get's teleported to a room filled with Alien Grunts, and he has no weapons, other than his HEV Mk. IV suit, and is presumably killed. Out of universe (real life), then yess, he will die multiple times, but thankfully, VALVe game him the "Quick Save" and "AutoSave" abilties lol.