This work proposes an unsupervised fusion framework based on deep convolutional transform learning. The great learning ability of convolutional filters for data analysis is well acknowledged. The success of convolutive features owes to convolutional neural network (CNN). However , CNN cannot perform learning tasks in an unsupervised fashion. In a recent work, we show that such shortcoming can be addressed by adopting a convolutional transform learning (CTL) approach, where con-volutional filters are learnt in an unsupervised fashion. The present paper aims at (i) proposing a deep version of CTL ; (ii) proposing an unsu-pervised fusion formulation taking advantage of the proposed deep CTL representation ; (iii) developing a mathematically so...