The Blue Dolphin is a nice restaurant, make no mistake. But, there is no dress code so to speak, and the atmosphere is pretty laid back. Brian and Karen intended for the bar and grill to be welcoming and relaxed, not uptight, so there is little fear of coming underdressed and sticking out like a sore thumb. A word of advice, though. While it is relaxed, it is very much a shoes and shirt place, not sandals and a bare chest. Just because you are eating excellent food does not mean you need to be wearing stuffy clothing, but you aren't on the beach either!