No, you do not necessarily need to file a tax return for a Dormant Company, but you need to notify HMRC in the correct way to avoid having to do so.
Why Do You Have to File a Tax return for a Dormant Company
If you have newly formed a Company but never traded through it you will probably receive a Notice to Deliver a Company Tax Return from HMRC. This is because when you register a new Company at Companies House, HMRCs default position is that all new registered Companies are trading and so need to file a Corporation Tax Return.
If you have a registered company which traded previously and now is dormant, then HMRC will continue to send you a Notice to Deliver a Company Tax Return because they assume that you have continued to trade as normal.
In both cases you can avoid having to file a tax return for a Dormant Company by getting in touch with HMRC.
How to Avoid Having to File a Tax Return for a Dormant Company
To avoid filing a Tax Return for a Dormant Company you need to contact HMRC by letter. My step by step guide contains a template you can use to write to HMRC and tells you the information you need to include with your letter as evidence of Dormant Company Status.