West Midlands Fire Service were called to the fire in Crown Street, in Heath Town, just after 9.30pm on Sunday.
The fire involved two large skip lorries and a single-storey industrial unit.
An investigation has now been launched into the cause.
A spokesman for West Midlands Police said: "Investigations into the cause of a severe fire in Heath Town, Wolverhampton are continuing today [Monday].
"We responded to the incident in Crown Street just after 9.30pm on Sunday, September 26. Our first crew arrived within three minutes of being mobilised.
"The fire involved two large skip lorries and a single-storey industrial unit.
"Our initial response included four fire engines, one Brigade Response Vehicle and an aerial hydraulic platform, crewed by 25 firefighters from Fallings Park, Wolverhampton, Tettenhall, Walsall and Dudley fire stations.
"The firefighting operation involved carefully cooling two gas cylinders which were found at the premises.
"Crown Street was closed in both directions.
"Overnight crews were relieved by day colleagues, and the last firefighting resources left the scene at around 11.15am on Monday."