Two new species of Begonia L. (Begoniaceae), B. laotica (sect. Parvibegonia) and B. hypoleuca (sect. Reichenheimia), from north Laos are described and illustrated. Begonia augustinei, B. dryadis, B. lancangensis, B. sizemoreae and B. sillentensis subsp. mengyangensis were newly recorded taxa in Laos. Furthermore, an updated checklist of Begonia of Laos is also compiled.