Blind image super-resolution reconstruction focuses on recovering Low-Resolution (LR) images into clear High-Resolution (HR) images in real-world scenarios. Most existing degradation estimation networks cannot accurately estimate the degradation information of LR images, and the traditional Residual-in-Residual Dense Blocks (RRDBs) in super-resolution networks have poor generalization ability, which fail to adapt to complex degradation types. To address the above issues, a blind image Super-Resolution reconstruction method by Integrating Degradation estimation and Dynamic residual-in-residual dense blocks (IDD-SR) was proposed. First, an integrating degradation estimation network was proposed and used for accurate estimation of image degradation information. Then, a Dynamic Residual-in-Residual Dense Block (DRRDB) was proposed to improve the universality of the super-resolution reconstruction network. Finally, accurate prediction of complex degradation information and high-quality super-resolution image reconstruction were achieved through end-to-end joint optimization. Experimental results on the Set14, BSD100, and DRealSR datasets demonstrate that the Peak Signal-to-Noise Ratio (PSNR) values of 4× super-resolution of IDD-SR are improved by 0.90 dB, 0.71 dB, and 0.97 dB, respectively, compared with those of PDM-SRGAN. It can be seen that the proposed method has superior detail recovery capability and artifact suppression effect.