Green tea is made from the leaves of the Camellia Sinensis plant without fermentation (Suzuki, Miyoshi & Isemura, 2012) and is considered a popular and healthy drink in Asian countries. due to its potential health benefits, such as protection against cancer and cardiovascular disease (Harvard Health Publications, 2012; Iwasaki et al., 2014). Many positive effects are due to the antioxidant activity of (-)-epigallocatechin gallate (EGCG), which is a major component of green tea (Suzuki et al., 2012). And this attracts the interest and attention of researchers to further their research. According to Suzuki et al., an example of the health benefits is that catechins found in green tea have an anti-obesity effect by stimulating lipid metabolism in the liver (2012). However, green tea can bring us undesirable results due to certain constituents. Caffeine is one of these diuretic substances and reduces the feeling of fatigue, but the consequences of overconsumption are well proven: it will reduce the duration of sleep and deteriorate the quality of sleep by causing insomnia (Suzuki et al., 2012 ). One study found that college students' tea consumption was significantly related to sleep quality (Cheng et al., 2012). However, the types of tea have not been studied. The effect of green tea consumption on sleep quality is not yet well documented. Sleep is very important for our body to relax and prepare for the next day. Unfortunately, poor sleep quality is prevalent in modern cities like Hong Kong. A growing number of college students have reported sleep problems. (Suen, Hon and Tam, 2008). Meerlo, Mistlberger, Jacobs, Heller & McGinty (2009) reported that prolonged sleep loss can affect the rate of neurogenesis...... middle of article ......p Medicine Reviews, 12( 2), 153- 162. Sereshti, H. and Samadi, S. (2014). Quick and easy determination of caffeine in teas, coffees and eight drinks. Food Chemistry, 158, 8-13. Suen, LK, Hon, KL and Tam, WW (2008). Association between sleep behavior and sleep-related factors among university students in Hong Kong. Chronobiology International, 25, 760-775. Suzuki, Y., Miyoshi, N., and Isemura, M. (2012). Health benefits of green tea. Proceedings of the Japanese Academy, 88(3), 88-101. Tseng, HC, Wang, C., Cheng, SH, Sun, Z. Chen, PS, Lee, C.,… Yang, Y. (2014). Tea drinking habit among new university students: associated factors. Kaohsiung Journal of Medical Sciences, 30, 98-103. Tsui, Y. and Wing, Y. (2009). A study on the sleep habits and problems of university business students in Hong Kong. American Academic Health Journal, 58(2), 167-176.