Police said the officers were killed in a shoot-out with suspected ethnic Pokot "bandits" in the Kamwenje area of Laikipia West.
"Six police officers have been killed, while four have been injured," said a senior police officer who asked to remain anonymous as he was not authorised to talk to the press.
Violence has spiked in Laikipia this year with smallholder farms and huge ranches alike invaded by armed herders.
Dozens of people have been killed and thousands displaced while a government-ordered security operation has so far failed to quell the unrest which some blame on drought and others on politics.
In a report this week advocacy group Human Rights Watch said the violence in Laikipia and neighbouring Baringo county had displaced people meaning they would be unable to vote next month.
"Kenya's government needs to lawfully address the security crisis in parts of the Rift Valley ahead of the August vote," said Africa researcher Otsieno Namwaya warning the insecurity "could have a serious impact on people's ability to vote in the August election.