Launching a report citing a "worrying increase" in racist incidents, he said racist-motivated crimes were actually down.
The minister said the rise documented in a Government advisory body report reflected greater reporting of incidents, not an increase in incidents.
He said the data also included incidents - such as discrimination and graffiti - which were not racist crimes as defined by garda statistics.
Mr McDowell said that, according to garda figures, there had been 42 race-motivated crimes so far this year. This was down from 69 in 2003 and 102 in 2002. Data published by the National Consultative Committee on Racism and Interculturalism (NCCRI) said 70 racist incidents had been reported to it between May and October this year, with a further 42 in the six months before that.
"I'm glad that more incidents are being reported, not in the sense that they are occurring, but that there is somebody to whom they can be reported," said Mr McDowell.
"Looking at the garda figures it would be a mistake to infer from increased reporting of incidents, including discriminatory incidents, through some kind of lazy mindedness, that racial violence is up. It's not. If you look at garda figures, it's on the way down." But NCCRI director Philip Watt said: "our report shows that much progress has been made in recent years to combat racism.
"However, there remains worrying signs of an increase in racism in recent times, with new forms of racism appearing, which means we need to redouble our efforts to ensure racism has no place in Ireland," he added.
According to the NCCRI data, almost two-thirds of the incidents occurred in Dublin and a further fifth in other urban areas.
The minister said he would look into a report published in Metro Éireann which found that a fifth of officers in the Garda Racial and Intercultural Office were members of the Garda National Immigration Bureau (GNIB).