Wonderworld was the last Uriah Heep album to feature bass player Gary Thain.

The album was remastered and reissued by Castle Communications in 1996 with four bonus tracks, and again in 2004 in an expanded deluxe edition.

AllMusic's retrospective review noted that "Wonderworld continues in the vein of Sweet Freedom, trying to bring Uriah Heep's appeal to a wider level while still retaining the grandiose trademark elements (the organ-guitar attack, David Byron's operatic shriek) that got them noticed".

Comparing it to the band's prior work, reviewer Donald A. Guarisco added that "The result is an album that is solid but not as inspired as Look at Yourself or Demons and Wizards.

[3] Martin Popoff found Wonderworld "conceptually vacant" and "lacking the fluid instrumental chemistry that loosely held together its predecessor", while still containing two gems in the songs "Suicidal Man" and "So Tired".