No, A Demat account isn’t required to acquire sovereign gold bonds.
It’s not necessary that you need to have a Demat account to acquire Sovereign Gold Bonds. If you have a Demat account, then whatever Sovereign Bond your purchase, then they would be stored in your Demat account where you can trade them on exchange. However, if you don’t have a demat account, you will need to fill out an application form and submit it to the post office, where you will get a certificate of holding, which is also issued by SHCIL offices, stock exchanges, and agents. An E-certificate will be shared to your email address by the RBI for the purchased sovereign bonds.