In this paper, we propose an efficient deepfake detection method using the Lottery Ticket Hypothesis (LTH) to address the threats to information integrity and social trust caused by the rapid increase in deep synthetic media. We conduct experiments by applying architectures such as MesoNet, CNN-5, and ResNet-18 to the OpenForensic and FaceForensics++ datasets, and show that it is possible to reduce the model size without performance degradation through neural network pruning. In particular, in the case of MesoNet, we achieve an accuracy of 56.2% on the OpenForensic dataset (about 90% compared to the baseline accuracy of 62.6%) even at a pruning ratio of 80%, and we obtain results using only 3,000 parameters. In addition, we show that the proposed LTH-based iterative size pruning method is superior to the batch pruning method, and we confirm that the pruned network focuses on the face region that is important for deepfake detection through Grad-CAM. We also show the transferability of winning tickets between datasets, suggesting the possibility of an efficient and deployable deepfake detection system.