Lindsay Lohan has been released from the hospital after totaling her car this afternoon in L.A.

A rep for Lindsay tell us, the actress was on her way to the "Liz & Dick" set when she plowed a rented Porsche into the back of an 18-wheeler -- smashing the car to pieces.

The rep says Lindsay was brought in to Santa Monica UCLA hospital as a precaution -- she had no serious injuries ... neither did Lindsay's assistant.

We're told Lindsay is fine and is now on her way back to the set ... in the back of an SUV.