Can Employment Pass (EP) holder apply for LTVP before the main pass (EP) application is approved?

Is LTVP allowed to be applied before approval of Employment Pass (EP) application?

Yes, you can.

However, MOM recommendation is to wait until after the main pass is approved. If the main pass application is rejected, your Long Term Visit Pass (LTVP) will also be rejected, and your application fee will not be refunded.