Automatic image annotation (AIA) has been adopted in different applications such as image retrieval and classification. Deep Learning is used in AIA to extract image features and then convert these features into text descriptions and labels. However, conventional AIA models that employ deep learning methods suffer from various shortcomings, such as poor annotation performance. This work proposes an AIA model based on convolutional neural networks (CNNs), generative adversarial networks (GANs), and transfer learning. GANs have attracted a lot of interest because of its ability to generate data without explicitly using probability density. Thus, it has proven its usefulness in image annotation and image augmentation. In this work, an Auxiliary classifier-GAN (ACGAN) has been used, where the discriminator predicts the class of an image rather than taking it as a given input; therefore, the stabilization of the training stage is ensured, and the generation of high-quality images is provided. Transfer learning is also used to enhance the performance of the classification. The proposed model outperforms the best state-of-the-art models in terms of MiAP, F-measure and error rate using ImageClef, ESPGame and IAPR-TC12 datasets.