By using ItemSource property you can bind treeview to Observable collection
For Eg:-
<treeview itemssource="{x:Static local:Window1.AnimalCategories}">
<treeview.itemtemplate>
<hierarchicaldatatemplate itemssource="{Binding Path=Animals}">
<textblock fontweight="Bold" text="{Binding Path=Category}" />
<hierarchicaldatatemplate.itemtemplate>
<datatemplate>
<textblock text="{Binding Path=Name}" />
</datatemplate>
</hierarchicaldatatemplate.itemtemplate>
</hierarchicaldatatemplate>
</treeview.itemtemplate>
</treeview>
for more information please check this link
WPF Treeview: Styling and Template Binding using MVVM[
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Thanks
Sujeet