Yes, you must declare dividends you receive on your tax return. You should receive a dividend statement indicating the amount of dividends paid to you and on what date.
You can receive dividends from a listed investment company, a public trading trust, a corporate unit trust, or a corporate limited partnership. Dividends may be paid in the form of money or property, including shares.
Do note that in Australia, dividends are taxed under an imputation system, by which companies pay tax on their dividends and then pass franking credits on to their shareholders along with the dividends they receive. If you receive dividends that have been franked, you may be able to receive a franking tax offset for the tax the company has already paid on those dividends.