‘EePi No.1’, a new mid-ripening cultivar of chestnut (Castanea crenata Siebold & Zucc.) was developed in 2000 by cross-pollinating two cultivars, viz., ‘Riheiguri’ and ‘Ganne’ at Korea National Institute of Forest Science. Line selection among the seedlings of ‘Riheiguri’ and ‘Ganne’ was carried out in 2007, followed by comprehensive evaluations of fruit morphological traits and tree growth characteristics conducted during 2008-2015. The harvest time of ‘EePi No.1’ was the first week of October. It is characterized by excellent nut quality, suitable for both raw consumption and processing. The average fruit weight was 24.0 g, which is significantly higher than that of the cultivar ‘Daebo’ (20.0 g). Moreover, the soluble solids content was 14.26%, and pellicle removability was 93.5%. This cultivar produces large, firm fruits with high sugar content, making it ideal for consumption. It is also characterized by excellent nut quality, suitable for both raw consumption and processing. Moreover, the easily peelable inner skin makes it ideal for processing and roasting, thereby enhancing its commercial value. These qualities are expected to bolster the diversification of income derived from forest products in the future (Registration No. 337).