A signal processing device processes a signal sent from an imaging device detachably attached to the signal processing device and includes: a signal processing unit configured to rewrite processing contents in accordance with a configuration configuration memories having different capabilities and configured to store pieces of configuration data corresponding to contents of image processes that are performed in accordance with imaging sensors held by the imaging devices a configuration controller configured to perform control to subject the signal processing unit to reconfiguration using the configuration data that depends on the imaging sensor of the imaging device attached to the signal processing device among the configuration data a priority setting unit configured to set priority for each configuration data based on a predetermined condition and a rewrite controller configured to rewrite the configuration data in the configuration memories based on the priority set by the priority setting unit.
