Duchenne and Becker muscular dystrophies (DMD/BMD) are the most commonly inherited neuromuscular disease. However, accurate and convenient molecular diagnosis cannot be achieved easily because of the enormous size of the dystrophin gene and complex causative mutation spectrum. Such traditional methods as multiplex ligation-dependent probe amplification plus Sanger sequencing require multiple steps to fulfill the diagnosis of DMD/BMD. Here, we introduce a new single-step method for the genetic analysis of DMD patients and female carriers in real clinical settings and demonstrate the validation of its accuracy. A total of 89 patients, 18 female carriers and 245 non-DMD patients were evaluated using our targeted NGS approaches. Compared with traditional methods, our new method yielded 99.99% specificity and 98.96% sensitivity for copy number variations detection and 100% accuracy for the identification of single-nucleotide variation mutations. Additionally, this method is able to detect partial deletions/duplications, thus offering precise personal DMD gene information for gene therapy. We detected novel partial deletions of exons in nine samples for which the breakpoints were located within exonic regions. The results proved that our new method is suitable for routine clinical practice, with shorter turnaround time, higher accuracy, and better insight into comprehensive genetic information (detailed breakpoints) for ensuing gene therapy.