This paper reports on and discusses the way professionals use metadiscourse in an attempt to achieve persuasion through workplace emails. Drawing upon the interpersonal model of metadiscourse, a total of 659 workplace request emails collected from professional contexts in Hong Kong were analyzed. The type and abundance of the various metadiscourse categories used in this computer-mediated communication genre were first identified and then compared with those found in non-computed mediated ones that also aim to persuade others. The results suggest (1) email offers professionals a convenient channel to persuade colleagues to comply with requests by appealing to rationality, credibility and emotions; (2) persuasive attempts made via email differ from those made via other channels in terms of the pattern of use of metadiscourse; and (3) there may be a preferred pattern of use of persuasive strategies in different moves of the workplace request email genre.