Hi RPA,

I have created a sample that full-fill your requirement.

You need to set the HtmlEncode property to false for the Height BoundField like below and call the databind.

HTML

<asp:GridView ID="gvDetails" runat="server" AutoGenerateColumns="False">
    <Columns>
        <asp:BoundField DataField="Id" HeaderText="ID" Visible="false" />
        <asp:BoundField DataField="Height" HeaderText="Height" HtmlEncode="False" />
        <asp:BoundField DataField="Name" HeaderText="Name" />
    </Columns>
</asp:GridView>

Code

protected void Page_Load(object sender, EventArgs e)
{
    DataTable dt = new DataTable();
    dt.Columns.AddRange(new DataColumn[3] {new DataColumn("Id", typeof(int)),
	                                new DataColumn("Name", typeof(string)),
	                                new DataColumn("Height", typeof(string)) });
    dt.Rows.Add(1, "Firuz", "95kg<br/>85sm<br/>45mt");
    dt.Rows.Add(2, "Asror", "95kg<br/>85sm<br/>45mt");
    dt.Rows.Add(3, "Sadriddin", "95kg<br/>85sm<br/>45mt");
    this.gvDetails.DataSource = dt;
    this.gvDetails.DataBind();
}

Screenshot