Activating mutations in the epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) are significant oncogenic drivers in non-small cell lung cancer (NSCLC) patients. Despite several approved EGFR and ALK inhibitors, drug-resistant mutations pose a major challenge. Especially, there is currently no approved EGFR inhibitors targeting the C797S mutation, a refractory mutation resistant to the third-generation EGFR inhibitors. Furthermore, an increasing number of patients with EGFR/ALK co-mutations have been identified in clinical practice, yet there are no effective therapeutic options available for them. In this study, we report the discovery and preclinical evaluations of a new small-molecule drug candidate, DA-0157, which is capable of overcoming EGFR drug-resistant mutation C797S and EGFR/ALK co-mutations. DA-0157 demonstrated excellent in vitro efficacy, significantly inhibiting various EGFRC797S mutants resistant to the third-generation EGFR inhibitors, ALK rearrangements, and EGFR/ALK co-mutations. In vivo studies revealed that DA-0157 substantially inhibited tumor growth in the LD1-0025-200717 EGFRDel19/T790M/C797S PDX model (40 mg/kg/d, TGI: 98.3 %), Ba/F3-EML-4-ALK-L1196 M CDX model (40 mg/kg/d, TGI: 125.2 %), and NCI-H1975 EGFRDel19/T790M/C797S & NCI-H3122 (EML4-ALK) dual-side implantation CDX model (40 mg/kg/d, TGI: 89.5 % & 113.9 %). DA-0157 demonstrates favorable pharmacokinetic properties and safety. Currently, DA-0157 (DAJH-1050766) is undergoing Phase I/II clinical trials.