what are some couples that are still together that met as a male and female lead on a drama.

Zanilia Zhao and William Feng 

They have been in quite a number of dramas together but I believe that their most famous work is The Story of Ming Lan.

Luo Jin and Tiffany Tang. They met during the recording of The The Princess Wei Young , they are married and had their first child together recently.

Leo Li (Li Jia Ming) and Liu Yong Xi. They met during the recording of Moonshine and Valentine  in 2018, they announced their relationship this year and recently married :))

Chen Xiao and Michelle Chen who met while recording The Romance of the Condor Heroes  in 2014, they married in 2016.

Lee Bo-young and Ji Sung met in Save the Last Dance for Me (she's the second lead, though) in 2004, got married in 2013

Han Ga-in and Yeon Jung-hoon met in Yellow Handkerchief (they're supporting characters, not leads) in 2003, got married in 2005

Song Yoon-ah and Seol Kyung-gu acted together twice--in the movies Jail Breakers in 2002 and Lost in Love in 2006--and they got married in 2009

Maeda Atsuko and Katsuji Ryo acted together in Dokonjo Gaeru in 2015, got married in 2018

Eikura Nana and Kaku Kento met in N no Tame ni in 2014, got married in 2016

Bonus: Yamaguchi Momoe and Miura Tomokazu met in the set of Izu no Odoriko in 1974, made a string of movies together, and have been married for forty years; she left show business when she married him, though