The document describes research on improving lung nodule detection accuracy using an effective 3D CNN framework. The proposed MR3DCNN-KT model aims to capture contextual information between slices using 3D CNN. It also aims to reduce false positives and negatives through an iteratively optimized deep learning method and reduce 3D CNN complexity. Experimental results on a lung CT dataset show the MR3DCNN-KT model achieves higher accuracy, precision, recall, and F-measure than existing methods, demonstrating its effectiveness in automatic lung nodule detection.