Supreme Court judge Robert Hulme on Friday knocked back Flower's second bail application since he was arrested in May over his alleged involvement in an international drug cartel.

The 47-year-old appeared via videolink from Long Bay prison wearing prison greens but was supported in court by his wife Camilla, who broke down in tears during the brief hearing.

"The prosecution case is a strong one," Justice Hulme said.

"The offences alleged are of very grave seriousness. The applicant faces potential incarceration for a very long time, with the maximum penalty prescribed for some of the offences being life imprisonment.

"I am not satisfied that the applicant has shown cause why his detention is not justified. The application for release on bail is refused."

Flower is facing two charges of importing a commercial quantity of a border-controlled drug related to the smuggling of 38 kilograms of cocaine into Australia via Sydney International Airport in April and May this year.

He has also been charged with one count of engaging in business to import a commercial quantity of border-controlled drugs and two counts of dealing with the proceeds of crime after police allegedly found over $150,000 in his car and house.

The court heard that his trial is unlikely to commence until early 2021 and will last two to three months.

It's alleged that Flower had a principal role in an international drug ring which imported drugs from South Africa over a three-year period.

"It may be inferred from this that he has considerable criminal associations both in Australia and overseas," Justice Hulme said.

Police allege that Flower's co-accused, Qantas baggage handler John Mafiti, would pick up duffel bags - sent as unaccompanied baggage from South Africa - containing drugs and escort them out of the airport.

The pair met while Flower worked as a baggage handler from 2000 to 2004 and it's alleged they communicated using covert phones in coded language.

"As is found in many drug cases, the participants obviously did not realise how crude and obvious their attempts to conceal the true meaning of their communications were," Justice Hulme said.

The Crown will argue that the drug ring attempted or carried out the importation of drugs on 45 occasions but Flower has only been charged with two counts of importing drugs.

Flower's lawyers applied for bail on the grounds he could offer a substantial surety, has a limited criminal history and was described as a "responsible family man and business owner".

However, Justice Hulme said he was facing serious charges and the case against him was strong enough for him to be denied bail.

Flower rose to prominence in racing with Group One-winning horse Snitzel, which is now Australia's champion stallion commanding $40 million a year in service fees.

He's since established a training facility on Sydney's northwest fringe for his stable of racehorses.

Racing NSW on May 23 stood Flower down from participating in the state's racing industry, banned his racing colours and ordered any prize money earned from his horses be withheld until the court case is finished.

He's due to appear in Central Local Court for committal in late January.

Australian Associated Press