Biospeckle is a phenomenon generated by laser light scattering in biological tissues or surfaces. The shape and intensity of speckle pattern vary with time, and this variance is believed to have relation with the biological activity of the sample. Biospeckle is a kind of optical measuring technology which has many advantages such as whole field measuring, non-contacting, real time, etc. Hence it is applied widely in the areas of biomedicine and agriculture. A brief introduction to the theory is presented. The research progress and achievements are also introduced. The theory and characteristic of main image processing methods are analyzed and compared.