Scholars　have　not　reached　a　consensus　to　date,　although　they　have　tested　the　Porter　Hypothesis　widely.　This　inconsistency　may　come　from　the　overlooking　on　the　complexities　of　the　causal　chain　involved　in　the　Porter　Hypothesis.　Therefore,　the　purpose　of　this　article　is　to　reexamine　the　Porter　Hypothesis　in　a　contingency　view　by　introducing　slack　resources　as　moderators.　Employing　data　of　20　Chinese　pollution-intensive　industrial　sectors　from　2001　to　2010,　we　find　that　environmental　regulation　has　a　positive　impact　on　innovation,　and　innovation　has　a　positive　influence　on　competitiveness.　Additionally,　the　relationships　in　these　two　stages　are　moderated　by　different　slack　resources　to　varying　degrees.　In　the　first　stage,　unabsorbed　slack　resources　play　a　stronger　positive　moderating　role　than　do　absorbed　slack　resources.　In　the　second　stage,　the　relationship　between　innovation　and　competitiveness　is　significantly　and　positively　moderated　by　unabsorbed　slack　resources,　while　absorbed　slack　resources　present　an　insignificant　moderating　effect.　©　2020　ACM.