Boohoo's CEO John Lyttle will step down as the British fashion firm prepares for a strategic review.
The company, which also owns the brands PrettyLittleThing, Debenhams, and Karen Millen, said that its operations require an overhaul "to unlock and maximise shareholder value".
Currently, it stated that its business remains "fundamentally undervalued".
Although Boohoo profited from an online shopping surge during the pandemic, it has since underperformed against Chinese rivals like Shein and Temu.
Supply chain problems and higher product returns have also hit the firm's margins, while consumer demand has been dampened by wider economic conditions.
Boohoo's gross merchandise value after returns dropped by 7% to £1.2bn (€1.4bn) in the six months to the end of August.
Adjusted profits, meanwhile, fell 32% to £21m (€25.3m).
Full first-half results will be published next month.
Lyttle, who has led Boohoo for five years, will continue his duties until a successor is found.
Boohoo has also agreed a new £222m debt refinancing to finance its transformation.
The group's share price was down by around 5% in daily trading as of around 15h30 CEST, at £30.10 (€36).