try this , you could always play with datatypes once you have data in your table..

string constr = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\\Documents\\Book1_3.xlsx;Extended Properties='Excel 12.0;HDR=NO;'";

OleDbConnection con = new OleDbConnection(constr);

con.Open();

DataTable dt = con.GetOleDbSchemaTable(OleDbSchemaGuid.Columns,null);

con.Close();

SqlConnection sqlcon = new SqlConnection("Server=servername;Database=dbname;Trusted_Connection=True;Integrated Security=SSPI;");

string tblcreate = "Create Table ##TEMP_Excel(";

foreach (DataRow dr in dt.Select("TABLE_NAME='Sheet1$'"))

{

tblcreate = tblcreate + dr["COLUMN_NAME"].ToString() + " varchar(32)" + ",";

}

tblcreate=tblcreate.Substring(0, tblcreate.Length - 1);

tblcreate = tblcreate + " );";

sqlcon.Open();

SqlCommand cmd = new SqlCommand(tblcreate, sqlcon);

cmd.ExecuteNonQuery();

sqlcon.Close();