To investigate the optimum harvesting time of rice from June to December 2015 at Yezin in Middle plain area of Myanmar. The rice cultivars tested were Dasan2, Yeongpungbyeo(Korean cultivars) and Shwe Thwe Yin(Myanmar cultivar). The ripened grain rate were high when the harvesting date after heading were between 35 and 40 days for Dasan2, Yeongpungbyeo and between 30 and 35days for Shwe Thwe Yin, respectively. The highest yield of rice was obtained when harvested 35 to 40days after heading for all cultivars. However, the shattering loss was the highest in 40days after heading, the yield losses in 40DAF(days after flowering) are 2 to 2.7 times more than other treatments in 30DAF. Therefore, the estimated optimum harvesting times are 40DAF, 31DAF and 25DAF for Dasan2, Yeongpungbyeo and Shwe Thwe Yin, respectively.