Here is the LINQ to convert your LINQ result into a comma separated value: string returnVal = (from a in b select a.StringValue).Aggregate(new StringBuilder(), (c, d) => c.Append(",").Append(@"""" + d + @""""), (c) => c.ToString().TrimStart(new char[] { ',' }) .TrimEnd(new char[] { ',' })) Here "b" is the list and StringValue will be the value which want to get converted to comma separated values.