Multiple instance learning (MIL) can be used for solving the imprecisely labeled hyperspectral target detection problems, which only needs the label of an area containing some targets. Furthermore, existing methods decompose this task into a target signature learning task and a follow-on similarity measurement between the estimated signature and the test points. In this paper, we propose a deep multiple instance learning method based on self-attention mechanism, in which the max operation and 1D convolution neural network (1D CNN) are adopted to realize an end-to-end hyperspectral target detection structure without learning the target signature. In the proposed deep MIL target detection method, self-attention mechanism with max operation has advantage in estimating the labels of instances from the positive bag via calculating the contribution of each instance to the bag-level classification. The simulated and real hyperspectral target detection experiments are shown to illustrate the performance of the method.