The race was red flagged on the opening lap as Grosjean hit the barrier, causing his car to erupt into flames.
The rest of the field returned to the pit lane as medics attended to the Haas driver, who soon emerged from the wreckage.
"I’m so grateful Romain is safe,” Hamilton wrote on Instagram.
READ MORE: Grosjean’s horror crash in pictures
“Wow… The risk we take is no joke, for those of you out there who forget that we put our life on the line in this sport and for what we love to do.
“Thankful to the FIA for the massive strides we’ve taken for Romain to walk away from that safely.”
After Grosjean was out of his car and speaking to medics, Haas said: “Romain has some minor burns on his hands and ankles but otherwise he is ok. He is with the doctors just now.
“As a precaution and for further medical evaluation Romain will be transported to hospital.”
Williams driver George Russell also expressed his relief at the news that Grosjean had emerged from the crash without serious injuries.
“Massive relief to see Romain is ok,” he wrote on Twitter.
“Huge credit to all the teams, the FIA and F1 for all the safety measures we have in the sport today.”
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