A superb Claudio Lopez hat-trick fired the Roman outfit into a seemingly unassailable 3-0 lead early on, however the Giuseppe Meazza side showed tremendous spirit to earn a draw.
The former Valencia forward was at his very best, netting his hat-trick is just 28 first half minutes.
The Argentine international netted his first from the penalty spot after nine minutes, and scored his second and third after 31 and 37 minutes.
Inter however, were not going to lie down and pulled a goal back on 38 minutes when Portuguese defender Fernando Couto inadvertently re-directed the ball into his own net.
Turkish international midfielder Emre pulled another goal back for the visitors on 67 minutes.
Lazio could have sealed the win, however Bernardo Corradi saw his effort cannon off the bar.
The visitors made the Romans pay for their miss and levelled matters when Emre netted his second of the game on 77 minutes - silencing the home crowd.
Elsewhere, Milan capitalised on Lazio's slip-up by assuming first place in Serie A, with a solitary Filippo Inzaghi goal handing them all three points in a 1-0 home win over struggling Roma.
Click here for Serie A match summaries:
Lazio 3-3 Internazionale
Milan 1-0 Roma
Click here for an updated Serie A table.
