Abstract: Non-destructive testing technology plays a vital role in the field of food quality evaluation, especially in the rapid and accurate detection of fruit sweetness. Traditional destructive testing methods are not only time-consuming and labor-intensive but also fail to meet the demands of modern rapid and efficient processes. With the development of spectroscopy, imaging technology, and electronics, non-destructive testing technology has gradually become a research hotspot. Fruit sweetness, as one of the important indicators for evaluating fruit quality, has significant implications for fruit grading, packaging, storage, and transportation. This paper explores the current research progress of non-destructive testing technology for fruit sweetness, analyzes its advantages and limitations, and looks forward to future development directions, aiming to provide a scientific basis for enhancing the competitiveness of the entire fruit industry.