private void Form1_Load(object sender, EventArgs e)
{
    fpSpread1.ActiveSheet.ColumnHeader.Rows[0].Renderer = new myColumnHeaderRenderer();

    fpSpread1.ActiveSheet.Columns[0].AllowAutoSort = true;

}

public class myColumnHeaderRenderer : FarPoint.Win.Spread.CellType.FlatColumnHeaderRenderer
{
    public override void PaintCell(Graphics g, Rectangle r, FarPoint.Win.Spread.Appearance appearance, object value, bool isSelected, bool isLocked, float zoomFactor)
    {
        FarPoint.Win.Spread.SortState sortState = appearance.SortState;
        appearance.SortState = FarPoint.Win.Spread.SortState.None;  //정렬 표시기를 그리지 않습니다.
        base.PaintCell(g, r, appearance, value, isSelected, isLocked, zoomFactor);
        appearance.SortState = sortState;
    }
}