The union has also reiterated the fact that farmers have a legal right to shoot a dog involved in sheep worrying.
Last year some 179 instances of livestock worrying, where animals have been hurt or killed, were reported in Scotland. That was up by 46 on the previous year.
The most affected areas were the Highlands and Islands, with 36 cases, and the Lothians and Borders area, where there were 27 cases. Aberdeenshire and Moray area came in third with 22 incidents.
In order to deal with the problem, the union is, for the second year running, supporting a multi-partner awareness-raising campaign by the Scottish Partnership Against Rural Crime.
Ayrshire farmer Jimmy Ireland has personal experience with dogs worrying sheep on his farm.
He said: “Sheep worrying continues to be a burden on us, and it is not just the financial losses we suffer, but the stress it can cause for sheep, and the time we have to take away from the day-to-day running of our business to deal with such cases.”
Gary Mitchell, NFUS vice-president, said: “The worrying of livestock can have devastating consequences for a farmer and their stock and as these statistics suggest, it is becoming an increasing problem.
“Sheep are particularly at risk during the spring lambing period and we need dog owners to take action to prevent livestock worrying, otherwise, if their dog is found worrying livestock they could face prosecution.”