The integration of biometrics and blockchain is proposed as a sophisticated and enduring security strategy to protect sensitive information in the digital era. 3D biometric data will not be affected by changes in posture and changes of illumination. This research proposed a security model for 3D multimodal (face and ear). To secure the 3D data uses the convolutional neural networks (CNNs) for 3D image feature extraction based on fusion of 3D face and ear data. Further compare the different hashing algorithms for the security of 3D multimodal Biometric model in Blockchain. This research also compares the different hashing algorithm efficiency and impact of blockchain mechanism on 3D face and ear data.