The men's and women's championships are organised by the International Boxing Association (IBA), the president of which is Russian Umar Kremlev. Russian energy company Gazprom is the IBA's biggest sponsor.
The boxing body has allowed boxers from Russia and Belarus to compete with their national flags and anthems, counter to International Olympic Committee (IOC) guidance following Moscow's February 24 invasion of Ukraine, which Russia calls a "special operation".
Swedish Boxing Federation chairman Per-Axel Sjoholm, referring to the long-standing complaints about the IBA, told news agency TT on Tuesday that there was "no democracy or transparency" in how it was run.
"We do not accept IBA's handling," he said. "We have been working for years to bring about a change, but without success."
"Then they themselves made the decision to allow Russia and Belarus to compete, moreover, under the national flag."
The women's championships in New Delhi on March 15-25 and the men's tournament is in Tashkent, Uzbekistan, in May.
The IBA has been at odds with Olympic organisers and it was stripped of involvement in the 2020 Tokyo Olympics.
Boxing is not on the initial programme for the 2028 Los Angeles Games, pending reforms demanded by the IOC following complaints about governance issues.
The IBA says the "significant progress" it has made has not been recognised by the IOC and it was clearing up a "tainted legacy" left by a former president.
The president of Boxing Canada, Ryan O'Shea, told the Canadian Press that Canadian boxers would also not be joining the amateur world championships.
"We've joined that movement," O'Shea said, referring to the boycott.
"We have significant concerns surrounding the risk our sport faces and its future within the Olympic lineup," he said.
Britain's governing body said its boxers would not participate in the women's championships and it was reviewing involvement in the men's tournament.
The United States, Ireland and Czech Republic will also be shunning both championships, their governing bodies said.
The IBA has warned that it would pursue "strong sanctions against those who initiate and join the participation boycott".
In December, the IOC raised the possibility of boxing being excluded from the 2024 Paris Games, accusing the IBA of having "no real interest" in the sport or its athletes.
Qualifying for Paris is being organised by the IOC.
