Bitcoin fell below $6,000 on Friday, but bitcoin bull Brian Kelly told CNBC that the popular cryptocurrency is "not dead."

"This is not the funeral for bitcoin whatsoever," Brian Kelly, founder and CEO of BKCM LLC, an investment firm focused on digital currencies, said on "Fast Money" Friday.

"Let's put this in perspective," he said. "Do you know where we were a year ago? $2,500."

Kelly said a combination of things — including tax selloffs, multiple exchange hacks and about $10 billion funding initial coin offerings (ICOs) — have caused the coin, the largest by market cap, to fall in price.

Still, investors might not be so certain. The coin fell below $6,000 in February. But at its highs, in December 2017, bitcoin was priced around $19,500. That translates to a price decline of more than 60 percent.

While Kelly said the drop is "painful," he also said it's not unusual.

Cryptocurrencies are in a bear market right now, he said.

"And bear markets, we don't know where they end," Kelly said. "It doesn't mean that bitcoin can't go lower. But this is by no means the funeral for bitcoin."