"The new WADA Code, which will come into force on 1 January 2015, will reflect our firm commitment to have tougher penalties and the IAAF will return to 4 year sanctions for serious doping offences," the IAAF said after its council met ahead of the world championships that start in Moscow on Saturday.
Athletics has recently been rocked by a string of doping cases, ranging from high-profile athletes like Tyson Gay, Asafa Powell and Veronica Campbell-Brown to tens of Russians and Turks, among others.
The IAAF cut the sanction to two years from four in 2004 in line with the World Anti-Doping Agency's thinking of the time, and has long called for a return to harsher punishement for doping infractions.
"The IAAF has an ethical obligation to the overwhelming majority of athletes and officials who believe in clean sport," it said.
"As a leader in this fight the IAAF has built and delivers a programme that is well resourced, far reaching, sophisticated and increasingly able to detect and remove from the sport those who breach our anti-doping rules."