Jatiya Party Presidium Member SM Faisal Chishty announced the support at the ruling party's Narayanganj office on Monday.
"She is a very qualified and skilled mayor candidate. We hope she will continue to improve the lives of the citizens of Narayanganj," Chishty added.
The Jatiya Party has not nominated any candidate for the first-ever polls to Narayanganj City on party lines.
Chishty said the Jatiya Party leaders and activists in Narayanganj had started soliciting votes for Ivy, who seeking a re-election.
Salim Osman, a member of the influential Osman family, is an MP from the Jatiya Party.
His brother AKM Shamim Osman, an Awami League MP, had earlier declared support for Ivy, signalling an end to the longstanding rivalry between the two Awami League groups in Narayanganj.