The pair was riding east on the Princes Highway, near Dore Road, at Pakenham when the officer, Sergeant Ken Rich, was hit by a Toyota Hilux ute about 8.50am.

Mr Rich's daughter cared for him at the scene until an ambulance arrived.

Paramedics worked on him for about an hour, but he died at the scene.

"He was out enjoying Good Friday with his family as most people are across the country," Assistant Commissioner Robert Hill said.

Sergeant Rich, who was said to be looking forward to his retirement and had only taken up cycling in recent years, was a father of five.

"The family is heartbroken. They are dealing with the loss of a husband and a father," Mr Hill said.

The officer had been in the force since 1980 and worked at the Narre Warren police station for 25 years.

"He was certainly well respected and well regarded," Mr Hill said.

"He was a member that was full of life, affable, a real personality around our police station.

Sergeant Rich was in "the twilight of his policing career" who was "looking forward to retirement, looking forward to spending time with his wife and children ... looking forward to travel and all of those things on our bucket list when we come to the end of our careers," Mr Hill said.

His colleagues were devastated at the tragic news.

"They have lost one of their members, one of their leaders, their friend," Mr Hill said.

"He was certainly well respected and well regarded.

"Road trauma, it doesn't discriminate."

Sergeant Rich's friends and acquaintances have left tributes on social media for him.

"A good man lost his life today," Simon Yeo said.

"Ken was swimming coach to our boys and President of the Cardinia Piranhas Swim Club. RIP."

Mandy Yeo wrote: "RIP Ken our thoughts with you and your family."

Angie King described him as a "wonderful man, brave, kind".

"Rest in peace, Ken Rich," she said.

"Thank you."

The officer and his daughter were cycling east, on the shoulder of the highway in a 100km/h zone.

The ute was also travelling east when it struck the officer, police said.

It has been reported the ute was trying to overtake the cyclists, when the side mirror of the vehicle hit Sergeant Rich.

The driver of the ute, a 58-year-old man from Pakenham, was not injured. He stayed at the scene and was assisting police with their inquiries.

Major collision investigation unit detectives are working to determine the cause of the crash.

Secretary of the Victorian Police Association, Sergeant Wayne Gatt sent his condolences to the officer's family.

"Earlier today, we learnt that one of our members was tragically killed in a road accident," he said.

"For the member's family, friends and close policing colleagues, the Easter period will now always be tinged with sadness. Our prayers and condolences are with them all, at this very difficult time."

Anyone who witnessed the crash or has any information is urged to contact Crime Stoppers on 1800 333 000.

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