GRAMERCY. For inexpensive Vietnamese eats, try this cool little Gramercy eatery located near the park. Although the place doesn't look like much more than your run-of-the-mill diner on the inside, L'Annam enjoys a loyal lunch following. Regulars love the light but spicy vegetarian entrées, especially such tasty options as their calamari salad, tofu steak and lettuce wraps. Reservations accepted. Casual dress. TRAIN: 6 to 28th St

UPPER EAST SIDE. A good start for those not familiar with Vietnamese food. Offerings include goodies such as green papaya salad, pork with garlic and sesame seed and pho bo, all served in a casual environment. Good prices for excellent food. Delivery service available. Business Casual dress. TRAIN: 6 TO 77th St

CHINATOWN. Though not much to look at on the outside, this Vietnamese restaurant remains popular thanks to its excellent dishes and reasonable prices. Among the regulars, favorites include staples like banh mi cary ga (curried chicken), the steamed fish for two, fried spring rolls, and barbecued pork chops. Make sure you head here early at lunchtime, as they tend to pack quickly. If the place is too crowded, walk over to the sister location at nearby 146 Centre Street (212-941-9292). Reservations are not accepted. TRAIN: J, M, Z to Canal St

CHINATOWN. In New York, this as close as you can get to Vietnam ­ from the thatched roof and mock courtyard to the carved artwork and bamboo walls. Of course, most of décor is faux, but the hordes of hungry regulars have never seemed to mind. Suggested dishes include such traditional favorites as day-pot fondues, spring rolls, pho (a beef stock soup), shrimp curry served over rice vermicelli, and barbecued beef wrapped in grape leaves. Reservations are accepted. TRAIN: J, M, N, R, Z, 6 to Canal St

UPPER WEST SIDE. Great prices and heaping portions are the rule at this small, unassuming Vietnamese restaurant. Although defined by some as rather dowdy in appearance, this eatery packs 'em in for its outstanding eats such as barbecue spareribs and grilled shrimp served on a bed of sugarcane. Reservations not accepted. Casual dress appropriate. TRAIN: 1, 2, 3, 9 to 86th St