Abstract: The physical properties of agricultural products are very important in many aspects, such as to determine some physical characteristics (such as shape, volume, size, density, porosity, color and appearance), fruit firmness, ripeness level and quality, to evaluate mechanical damage in grains, seed quality and integrity, genetic change and others. The present work is a review about some of the most commonly used physical properties of agricultural products such as electrical conductivity, optical properties, mechanical properties and thermal conductivity, which can be used in determining other parameters and properties such as the moisture content, density, microwave dielectric frequencies, ripeness levels, firmness and many other parameters in fruits, vegetables and grains. Many research results in this sector in the last three decades are also highlighted.