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High pressure processing (HPP) inactivates pathogens and increases the safety of ready-to-eat meat products. The high-pressure lethality and the behavior of the surviving cells after HPP depends on process parameters (pressure and time), microorganism and matrix characteristics. The aim of the present study was to quantify the impact of pressure level, water activity (<i>a_w</i>), and fat content on the behavior of <i>Salmonella</i> spp. and <i>Listeria monocytogenes</i> during refrigerated storage of dry-cured ham after high-pressure processing. <i>Salmonella enterica</i> serotype London CTC1003 and <i>L. monocytogenes</i> CTC1034 were inoculated at ca. 7 log cfu/g in dry-cured ham of different <i>a_w</i> (0.87–0.98), vacuum packaged, pressurized from 300 to 852 MPa for 5 min, and stored at 7 °C for up to 2 months. <i>Salmonella</i> and <i>L. monocytogenes</i> populations were monitored by plate count during the storage of the hams. The gamma concept was used to quantify the individual effects of <i>a_w</i> and storage temperature on the pathogen growth/no-growth behavior in pressurized dry-cured ham. The Weibull (inactivation) or Logistic (growth) primary models were fitted to the log change of pathogen levels during storage of dry-cured ham after pressurization. According to the gamma approach, the refrigeration temperature and <i>a_w</i> were the main factors limiting the growth of <i>Salmonella</i> and <i>L. monocytogenes</i>, respectively, in dry-cured ham. Under conditions not allowing growth, the effect of increasing pressures on the microbial inactivation depended on the <i>a_w</i> of dry-cured ham and the pathogen; dry-cured ham with high fat content with an <i>a_w</i> ≥ 0.95 enhanced the inactivation of <i>Salmonella</i> whereas it reduced that of <i>L. monocytogenes</i>. Under conditions allowing growth of <i>L. monocytogenes</i>, the increase in <i>a_w</i> from 0.96 to 0.98 reduced the lag time with no apparent impact on the growth rate.