Abstract The sea ice off East Greenland exhibits pronounced quasi‐decadal fluctuations superimposed on its long‐term decline. Here we show that this low‐frequency variability is tightly phase‐coherent with tropical Pacific quasi‐decadal variability (TPQD), revealing a teleconnection from the tropics to the Arctic. Using observations together with targeted pacemaker experiments, we demonstrate that convective anomalies during positive TPQD phases generate Rossby wave energy propagation along a Pacific–North American pathway, establishing a positive North Atlantic Oscillation (NAO)‐like circulation that enhances northward ocean heat transport into the Greenland–Iceland–Norwegian Seas. The resulting upper ocean warming drives sea ice loss along East Greenland, whereas the opposite circulation pattern during negative phases promotes cooling and sea ice growth, together producing quasi‐decadal fluctuations in local sea ice. These findings reveal a previously underappreciated tropical influence on Arctic climate and highlight a potential source of decadal predictability for Arctic change.