There are several choices. As everywhere in Iceland, the local gas station sells ice-cream, hotdogs and hamburgers.
You can also have pizzas and light meal at Allinn or Pizza 67 ( at the Aðalgatan, the high street of Siglufjörður and Rauðka, the red house at the harbor. In the easten part of the harbour you will find The Harbour House Cafe, which serves meals, beers and coffee.
For more refined dining, the Hannes Boy restaurant is located in the boat harbour, the yellow house next to Rauðka. Seat reservation is recommended.