Nineteen people were arrested in the western Turkish city of Izmir on Sunday, a day before Newroz celebrations for the Kurdish New Year, the DHA news agency reported.
Kurds in Turkey will welcome spring on Monday, celebrating the new year during the festival of Newroz, which translates as new day.
The arrests came ahead of planned demonstrations that could potentially turn violent as the event usually becomes an opportunity for political expression.
Among those held were two mayors of pro-Kurdish opposition party HDP, DHA said.
The authorities have banned Newroz festivities in the restive, largely Kurdish south-east of the country. Events are only being allowed in the Kurdish city of Diyarbakir on Monday, and tens of thousands are expected to attend.
The security situation has been tense for several months in the south-east, and the Turkish army said Saturday night that a soldier was killed in an attack by the banned Kurdistan Workers' Party (PKK) in Nusaybin.
In July last year, a two-year ceasefire between the PKK and the state collapsed after peace negotiations stagnated.
Many hundreds have died in the renewed conflict, mostly in the south-east, including civilians. There has been widescale destruction of neighbourhoods and hundreds of thousands have been displaced.
Following a series of bombings in Turkey and ahead of Kurdish New Year festivities, the umbrella group of the PKK issued a statement condemning attacks on civilians.
"The Kurdish freedom movement is opposed to attacks targeting civilians and condemns attacks on civilians," the statement said, noting that four people had died in a suicide bombing Saturday in Istanbul.
The PKK, which Turkey and some other countries list as a terrorist group, has been fighting the state for more than 30 years, amid accusations that the government discriminates against the Kurdish minority.
The militant group has modified its demands and is no longer demanding separatism, but has called for autonomy.
The statement from the PKK, carried by the pro-Kurdish Firat news agency, also condemned Turkey for allegedly killing civilians and said the group prefers peace to war but blamed the government for the collapse of peace talks.
Variations of Newroz are also celebrated in Syria, Iraq, Iran and the Caucuses.
Newroz festivities were banned in Turkey until 1995 when then prime minister Tansu Ciller declared that the festival was in fact a Turkic event. Despite a number of official celebrations of the festival, the vast majority of people who celebrate are of Kurdish origin.