The present invention provides amorphous form of Dronedarone or acid addition salt thereof. The present invention also provides amorphous co-precipitate of Dronedarone or its acid addition salts with a pharmaceutically acceptable excipient. A process for making an amorphous form of Dronedarone or acid addition salt thereof comprising providing a solution of Dronedarone or its acid addition salt in a solvent and removing the said solvent for isolating solid mass, which is the amorphous form of Dronedarone or its acid addition salt thereof. A process for preparation of amorphous co-precipitate of Dronedarone or its acid addition salts with a pharmaceutically acceptable excipient comprising preparation of a solution of the said Dronedarone or its acid addition salt and pharmaceutically acceptable excipients in at least one solvent and removal of solvent from solution obtained in step (a) for isolating solid mass, which is the amorphous co-precipitate of Dronedarone or its acid addition salts with the said pharmaceutically acceptable excipient.