Government attempts to boost their economies with monetary loosening could be “counterproductive”, Wolfgang Schaeuble told a conference ahead of a G20 finance ministers meeting in Shanghai.
But the US, Britain, EU and China all backed the use of monetary policy, while France gave Germany some support.
The gathering comes with the global economy assailed on multiple fronts, from slowing growth in host nation China to weak commodity prices, and after the OECD last week cut its 2016 global growth forecast from 3.3 percent to 3.0 percent.
Japan has already adopted negative interest rates, the European Central Bank has embarked on a huge quantitative easing programme and the US Federal Reserve has signalled possible delays to interest rate rises.
Schaeuble insisted that reforms were more important and “thinking about further stimulus just distracts from the real task at hand”.
Berlin does “not agree on a G20 fiscal stimulus package,” he said.
“Monetary policy is extremely accommodating to the point that it may even be counterproductive in terms of negative side effects.
– ‘No crisis' –
“Fiscal as well as monetary policies have reached their limits - if you want the real economy to grow there are no shortcuts without reforms.”
As the European Union's largest and richest country, Germany often has different economic priorities than other members, and Schaeuble's wide-ranging stance put him at odds with other key G20 members.
Speaking at the same conference, Bank of England governor Mark Carney retorted: “Several commentators are peddling the myth that monetary policy is out of ammunition.”
The world “risks being trapped in a low growth, low inflation and low interest rate equilibrium”, he said.
He criticised negative interest rates as a “zero-sum game” that exported problems to other countries, but said monetary stimulus “can buy time for structural adjustments” and the challenges “demand that our firepower is well aimed”.
– ‘Walking dead' –
In the US, Federal Reserve policymakers say economic risks have worsened since they lifted interest rates for the first time in more than nine years in mid-December.
US Treasury Secretary Jacob Lew told reporters: “It's increasingly important to use all the levers of policy that are available, and that means using fiscal levels as well as monetary policy and structural reforms.”
And Jeroen Dijsselbloem, president of the Eurogroup of single currency members said monetary policy had not come to the end of its usefulness.
“There is always more that can be done,” he said, adding: “It will have to be designed in a very proper way to…have the effects we need on economic growth.”
But French Finance Minister Michel Sapin offered his German counterpart some backing, saying there was “no crisis” in the world economy and “we don't have to put in action new policies”.
“We don't need to launch a global fiscal stimulus package,” he said in Hong Kong, but added some countries “may have more capacity and should use their budgetary capabilities to support global growth”.
Schaeuble, known for being frank, has previously openly criticised the ECB for being too accommodative.
The use of spending to mitigate against economic crisis no longer appeared to work, he said Friday, adding that debt levels were too high while growth remained too low.
“The debt-financed growth model has reached its limits,” he said. “If we continue on this path we no longer need to watch television, the walking dead will overwhelm us, particularly in finance and construction.”
He did not specify in which countries such zombie enterprises existed - although they are a perennial issue in current G20 president China.
The country is the world's biggest trader in goods, but its slowing growth has roiled global markets and sent prices of commodities such as base metals plunging, leaving producer countries facing a bleak outlook.
China's growth fell to 6.9 percent in 2015 - high compared to most other G20 members but the worst in a quarter of a century and a far cry from the fat years of double-digit increases.
A shock currency devaluation in August followed by another drop in January raised suspicions Beijing was pursuing a currency war to make its exports cheaper at others' expense, and a stock market slump has also raised alarms.
Beijing has more room to boost the economy, the governor of the central People's Bank of China said Friday as he sought to reassure markets.
“China still has some monetary policy space and monetary policy tools to address potential downside risk,” Zhou Xiaochuan said in a possible signal of more interest rate cuts and reductions in the amount banks must keep in reserve.
“We will not resort to competitive devaluations to boost our advantage in exports,” he added.