A total of 5,652 reports were submitted by local residents in 2020/21 - almost 2,000 more incidents than the previous year.
The majority of these - 2,629 - were on council land, more than 1,000 were on back alleyways and more than 700 on the highway.
Coun Jenny Platts, cabinet spokesperson for adults and communities, said the increase in incidents is due to coronavirus lockdowns and subsequent extra household waste.
She added: “Although locally and nationally we saw an increase in fly-tipping incidents in 2020/21, fuelled by the dramatic increase in household waste produced during the lockdowns, we are pleased to see that reports in Barnsley have been decreasing in recent months.
“Information about any person committing an environmental crime, including fly-tipping, can be sent to our teams at firstname.lastname@example.org.”