Based on field surveys in Lao PDR conducted during 2012 to 2017, ten new additions to the orchid flora of the country are reported: Bulbophyllum kingii, Cleisostoma nangongense, Dendrobium formosum, Dendrobium hesperis, Dendrobium linguella, Dendrobium pachyphyllum, Didymoplexiella siamensis, Hetaeria oblongifolia, Oberonia acaulis and Vanda coerulea. In addition, the following five names are found to be synonymous with four pre-existing taxa: Bulbophyllum manabendrae (=Bulbophyllum oblongum), Cleisostoma schoenorchaefolium (=Cleisostoma nangongense), Dendrobium abhaycharanii and Flickingeria xanthocheila (=Dendrobium calocephalum), and Habenaria yachangensis (=Habenaria dentata). Finally, two new combinations are made in accordance with current orchid taxonomy, namely, Vanda hienii (≡Ascocentrum hienii) and Robiquetia luongii (≡Malleola luongii).