Syntactic complexity has been extensively approached in the fields of corpus linguistics and academic discourse studies. However, works focusing on disciplinary variation in terms of linguistic complexity and comparison of professional and novice academic writing are scarce. Addressing these issues is likely to have important implications for EAP/ESP practitioners in terms of selection of target structures and learning material design. This study is a corpus analysis of the use of clausal complexity features in two social sciences, management and economics. The research is based on two kinds of corpora: expert corpora which comprise articles published in peer-reviewed journals, and learner corpora of L2 undergraduate students' research papers. This work aims at answering two questions: Do clausal complexity features vary in the texts in management and economics? What are the differences in syntactic use between the academic texts written by professional authors and learner writing? The data showed that economists and managers tend to use the structures under consideration with significantly different frequencies. The professional writing was found to demonstrate more signs of clausal complexity than the learners' texts.