Surin's food scene is solidly Isan: fiery, fermented, and cheap. The local style of som tam (green papaya salad) uses pla raa — fermented fish — rather than the milder fish sauce version popular in Bangkok, and the heat level assumes you can handle it.
The night market near the train station is the undisputed best option for an evening meal. For sit-down restaurants, the streets around the city's central fountain have several mid-range places serving both Thai and Isan food.