 <p>Yes. There is no requirement that <code>IDENTITY</code> columns be made a primary key.</p> <pre><code>CREATE TABLE T ( X INT PRIMARY KEY, Y INT IDENTITY(1,1) ) </code></pre> <p>Though I'm not sure when this would be useful. If you have a natural key that you want to use as the PK then you would probably want to put a unique constraint on the surrogate alternate key anyway.</p> <p>For purposes of setting up FK relationships SQL Server doesn't care if the column(s) is the PK or not it just requires a unique index on it/them.</p>