Andy Street said the Prime Minister's attention had been concentrated on taking a "world leadership" role at COP26 by securing agreements around the drive towards net zero.
He said the Paterson scandal – which saw the MP resign after he was found to have been paid for lobbying – needed to be "kept in perspective", claiming that voters in the West Midlands would judge the Government on its success in delivering "on the ground".
Mr Street arrived in Glasgow on Wednesday for a two-day stay at the conference, which he said had successfully "moved" a number of countries and businesses towards the changes needed to keep the 1.5 degree target within reach.
He told the Star: "There is this vast issue of climate change going on and all the international media are not remotely interested in Owen Paterson, they want to know if the British government is going to pull this off.
"Britain is taking a world leadership responsibility here and people are looking at the UK for its leadership ability and its diplomatic ability."
He said the PM was "to be admired" for putting "incredible political capital" on the line in leading COP26.
He said: "Some of the sort of missteps over the Owen Paterson thing probably reflect the fact that quite rightly, his brain has been elsewhere."
The Government has faced widespread criticism for forcing Tory MPs to back an amendment to save Mr Paterson's political career before a U-turn led to his resignation.
But Mr Street played down the long-term impact of the row, saying: "The Government is getting on and delivering on the ground in the West Midlands, and my honest view is that people across our region will judge the Conservative Party, its MPs and its councils on that."
He said the Government needed to make sure that MPs who did not stick to the rules were "dealt with", but that he "totally disagrees" with calls to ban MPs from having a second job.
"We often talk about our MPs having too narrow experience," he said. "If our MPs have one job outside parliament that pays relatively modestly but gives them good background experience, then that is a good thing and we mustn't lose that as a consequence of all this."
Mr Street said he had spent time at COP26 demonstrating the role the West Midlands can play in reducing carbon emissions through sustainable public transport and electric vehicles.
He said the region was building a funding "war chest" to combat climate change and had made huge strides forward in tackling the issue in recent years.
"We are seen to be playing a leading role in all of this," he said. "No one else has bid for the scale of hydrogen buses that we have. No one else has got the investment in the electric vehicle industry, and no one else has got the Beeching lines reopening to the extent that we are," he said.
The Mayor said plans were being discussed for a 'net zero neighbourhoods' scheme to retrofit homes, the first one of which was likely to be in the Black Country.