Pakistan became the first team to top the ODI team in ICC Rankings since ICC officially acknowledged them in January 2005 after beating the Kiwis in the fourth ODI. They improved their January 2007 number-three position.
Pakistan led the five-match ODI series 4-0 after beating New Zealand by 102 runs in Karachi on Friday.
Pakistan entered the series ranked fifth in ICC Rankings ODIs with 106.
The Men in Green have 113.483, surpassing Australia (113.286) and India (112.638).
Pakistan must win Sunday’s fifth and final ODI to stay on top. Australia will restore No.1 if they lose the last ODI.
Pakistan would also lead if they win the fourth ODI and the fifth match is abandoned or a no-result.