The Weald and Downland Living Museum in West Sussex has made 20% of its employees redundant after facing "severe financial strain" as a result of the coronavirus crisis.
The independent charity has experienced a "dramatic loss of income" as it relies heavily on revenue from ticket sales, courses, events and venue hire which have all been impacted by the lockdown.
The decision has been made to "safeguard the future of the museum".
The museum says it is reviewing other areas of the organisation such as its winter opening hours.
The open-air museum reopened to the wider public on Monday July 6 with strict safety measures and social distancing guidelines.
The charity added that these have been "incredibly difficult times, especially for local independent charities" which "really need the support of the public in order to get through these uncertain times".