The Ning-Wu Basin is the important parts of the Middle-Lower Yangtze River Valley metallogenic belt, where there are widespread porphyry-like type iron deposits. However, the researches on precise ore-forming epoch and tectonic setting are very weak. Based on detailed field geological work, we present new 40Ar-39Ar phlogopite ages for the typical Taocun, Baixiangshan and Hemushan iron deposits to constrain the timing and duration of mineralization in the basin. Phlogopite from the Taocun, Baixiangshan and Hemushan iron deposits yielded 40Ar-39Ar plateau ages of 129.3±1.1Ma, 130.7±1.1Ma and 129.1±0.9Ma, respectively. The dating result indicates that different porphyry-like type iron deposits in the Ning-Wu Basin are all formed in early stage of Early Cretaceous about 130Ma and obviously later than skarn-porphyry Cu-Au deposits related to high-k calc-alkaline intrusions in uplift areas. The porphyry-like type iron deposits in Ning-Wu volcanic basin were thought to be formed under regional lithospheric and thinning environment.