The 33-year-old All Black is out of contract at the end of the season but Johnson has no intention of letting Holah fly the nest.
Johnson, who is in his first full season in charge of the Ospreys, believes Holah can continue to play a huge role in the success of the Welsh region and he hopes to tie the openside to a new contract later this week.
"You only have to spend five minutes in Marty's company to see what he brings to our squad," said Johnson.
"He's tough, resilient and the ultimate professional and, in professional sport, you can't have enough Marty Holah's. He's a special player and man."
Holah looks likely to be offered a one-year extension to his current deal as the Ospreys look to regain the Magners League crown they won in 2007.
The former Wales coach admits that Holah's age means he is coming towards the end of his career but he is hopeful that he can persuade the popular Kiwi to commit to another 12 months in Swansea.
"We will sit down with Marty and see how he is feeling physically," added Johnson.
"But I love him and we definitely want to keep him.
"He is a wonderful human being and rugby player. It's a great combination."
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