Can I put external look up relation between external object and standard or custom object in Salesforce?

Hi abhi,

You can create an Indirect Lookup Relationship for that.It links a child External object to a parent Standard or Custom object. External child object’s indirect lookup relationship field will be mapped to custom unique + external Id on parent object.

Now let us discuss in detail about indirect lookup relationship configuration with an example.

Below example shows an Order (External Child Object) associated with Account (Standard Salesforce Parent Object).

Thanks.