I wouldn't unless that publisher is very reputable--and even then, I might think about getting an agent when an offer is on the table.
If you're inexperienced with anything related to publishing, you might want to go for an agent. If you don't know what you're doing when working directly with publishers, you can strike a bad deal, a bad contract, and all sorts of bad down the road. Agents are beneficial in this regard.
And honestly, I don't see a reason to not go for an agent; they can get you into better publishers, bring your MS to better editors, pull out better deals and contracts, avoid legal problems, and work with you on multiple projects to multiple publishers.
