Title: ChemistryQA: A Complex Question Answering Dataset from Chemistry. Abstract: Many Question Answering (QA) tasks have been studied in NLP and employed to evaluate the progress of machine intelligence. One kind of QA tasks, such as Machine Reading Comprehension QA,  is well solved by end-to-end neural networks; another kind of QA tasks, such as Knowledge Base QA,  needs to be translated to a formatted representations and then solved by a well-designed solver. We notice that some real-world QA tasks are more complex, which cannot be solved by end-to-end neural networks or translated to any kind of formal representations. To further stimulate the research of QA and development of QA techniques, in this work, we create a new and complex QA dataset, ChemistryQA,  based on real-world chemical calculation questions. To answer chemical questions, machines need to understand questions, apply chemistry and Math knowledge, and do calculation and reasoning. To help researchers ramp up, we build two baselines: the first one is BERT-based sequence to sequence model, and the second one is an extraction system plus a graph search based solver. These two methods achieved 0.164 and 0.169 accuracy on the development set, respectively, which clearly demonstrate that new techniques are needed for complex QA tasks. ChemistryQA dataset will be available for public download once the paper is published.