Quantitative　ultrasound　is　a　cutting-edge　ultrasound　technology　which　can　measure　quantified　information　related　to　tissue　or　material　microstructures　from　ultrasound　backscattered　signals.　Ultrasound　scatterer　size　is　an　important　quantitative　ultrasound　parameter　that　has　been　extensively　utilized　in　ultrasound　tissue　characterization,　including　disease　diagnosis,　treatment　monitoring,　and　efficacy　evaluation.　This　paper　aims　to　provide　an　updated　review　on　the　development　of　scatterer　size　estimation　for　ultrasound　tissue　characterization.　Firstly,　the　theory　of　sound　scattering,　ultrasound　backscattering,　and　backscattered　power　spectra　was　revisited.　Next,　the　methods　for　estimating　scatterer　sizes　from　ultrasound　backscattered　signals　were　categorized　and　introduced.　Subsequently,　the　applications　of　scatterer　size　estimation　in　ultrasound　tissue　characterization　were　reviewed.　Finally,　the　discussion　on　scatterer　size　estimation　in　ultrasound　tissue　characterization　was　presented　and　future　developments　were　suggested.　This　survey　may　be　helpful　for　researchers,　technicians,　or　clinicians　interested　in　quantitative　ultrasound,　particularly　in　scatterer　size　estimation　for　ultrasound　tissue　characterization.