Hi sanjoyp7er,
Its not possible to display as single CheckBox List.
You can change the RepeatDirection and RepeatColumns by setting its property.
Set RepeatDirection="Horizontal"
and RepeatColumns="5"
to display as two line.
HTML
<asp:CheckBoxList ID="CheckBoxList1" runat="server" AutoPostBack="True" Height="19px"
RepeatDirection="Horizontal" RepeatColumns="5" Width="506px">
<asp:ListItem Text="CC1" Value="10"></asp:ListItem>
<asp:ListItem Text="CC2" Value="20"></asp:ListItem>
<asp:ListItem Text="Bch12" Value="30"></asp:ListItem>
<asp:ListItem Text="Bch13" Value="40"></asp:ListItem>
<asp:ListItem Text="Bch14" Value="50"></asp:ListItem>
<asp:ListItem Text="dd1" Value="10"></asp:ListItem>
<asp:ListItem Text="dd2" Value="20"></asp:ListItem>
<asp:ListItem Text="dch12" Value="30"></asp:ListItem>
<asp:ListItem Text="dch13" Value="40"></asp:ListItem>
<asp:ListItem Text="dch14" Value="50"></asp:ListItem>
</asp:CheckBoxList>
Screenshot
