Contrastive learning has seen increasing success in the fields of computer vision and information retrieval in recent years. This poster is the first work that applies contrastive learning to the task of product matching in e-commerce using product offers from different e-shops. More specifically, we employ a supervised contrastive learning technique to pre-train a Transformer encoder which is afterwards fine-tuned for the matching problem using pair-wise training data. We further propose a source-aware sampling strategy which enables contrastive learning to be applied for use cases in which the training data does not contain product idenifiers. We show that applying supervised contrastive pre-training in combination with source-aware sampling significantly improves the state-of-the art performance on several widely used benchmark datasets: For Abt-Buy, we reach an F1 of 94.29 (+3.24 compared to the previous state-of-the-art), for Amazon-Google 79.28 (+ 3.7). For WDC Computers datasets, we reach improvements between +0.8 and +8.84 F1 depending on the training set size. Further experiments with data augmentation and self-supervised contrastive pre-training show, that the former can be helpful for smaller training sets while the latter leads to a significant decline in performance due to inherent label-noise. We thus conclude that contrastive pre-training has a high potential for product matching use cases in which explicit supervision is available.