The Jan 31 rally in Muang district was intended to be a mass gathering of red-shirts from across the country.
Mrs Tida said the rally had been cancelled because of concerns that it could be targeted by troublemakers, but she encouraged red-shirts to hold rallies in their home provinces in support of the Feb 2 general election.
She said information obtained by core UDD leader Jatuporn Prompan indicated that people were plotting to create unrest at the rally, adding that red-shirts from other provinces may have struggled to get to Bang Pu and locate the rally site.
"We reached a conclusion last night that we should not risk facing off with hooligans. We want to avoid unnecessary violence and casualties which could affect the election," Ms Tida said.
The UDD chair urged the red-shirts to monitor the situation at polling units on Feb 2 to help prevent any untoward incidents.