The Austrian three-time world champion was speaking after Sunday’s Singapore Grand Prix, in which Hamilton displayed blistering pace to pull away from the pack following a safety car period.
The Brit built a lead in excess of 20 seconds over second-placed Sebastian Vettel, then easily passed the German when back on track. His win was particularly significant for Mercedes following team-mate Nico Rosberg’s early retirement with technical troubles.
“He’s worth his money I can tell you that!” Lauda said to Sky Sports.
“When you have one car remaining and this is your only weapon out there you have doubts in everything. Constant doubting,” he continued.
“It was clear that when we saw the pitstop was okay he came out two seconds behind Sebastian that he would probably pass him, but there’s always a doubt.”
Mercedes boss Toto Wolff was also quick to praise Hamilton’s performance, which has piled further pressure on team-mate Rosberg .
“That was really awesome,” he said post-race.
“These are the Lewis Hamilton days. These are the days when you recognise how great he is and it makes the difference between the superstars and the stars.”
Hamilton leads the standings by three points from Rosberg with five races remaining, the last of which in Abu Dhabi will award double points.