The team artificially inseminated the female panda twice, on Sept 28 and 29, with sperm from her sleepy mate Xuang Xuang in the hope of another success, following the birth of Lin Ping.
The pregnancy was confirmed but the research team had now found evidence of a miscarriage in discharges from her genital area.
The general behaviour and eating habits of the 12-year-old panda had again become normal, similar to when she was not pregnant.
Mr Baripat said all indications were that she suffered a miscarriage and part of the embryo had been ejected and some of it had been re-absorbed into her body.
The team would again try to artificially inseminate her a later date, despite the unsuccessful attempt this time.
Thai-born female panda Lin Ping was born after the Lin Hui was artificially inseminated at the zoo in 2009. Lin Ping, aged 4, was sent to China last year to find her mate and It is hoped she will accept a mate and that the pair will return to Thailand after a year in China.