The Election Commission's decision is "unfortunate", highly arbitrary, motivated and "biased" and was taken at the behest of the BJP, she said in the letter, content of which was shared with PTI.
She has asked the poll panel to review its decision and also initiate a probe as to how and under whose guidance the decision of the transfers was taken.
"I strongly feel that the EC plays a neutral role to save democracy in India. But, it is very unfortunate that I have to write this letter today to raise strong protest against the transfer order dated April 5, 2019 issued by the EC by way of removing four senior officers from their existing positions," Banerjee wrote in her letter.
"The decision of the Commission is highly arbitrary, motivated and biased. We have every reason to believe that the decision of the Commission is at the behest of the ruling party at the Centre, i.e the BJP," the letter read.
The EC on Friday night removed Kolkata Police Commissioner Anuj Sharma and Bidhannagar Police Commissioner Gyanwant Singh in a major shake-up in the police establishment of the state.
Dr Rajesh Kumar, Additional Director General of Police (ADG), Pollution Control Board, was made the new Kolkata top cop, while Natarajan Ramesh Babu, ADG and IGP, Operations, was named the new Bidhannagar police commissioner.
The poll body named Avannu Ravindranath, DC (Airport Division) of Bidhannagar, as the new superintendent of police (SP) of Birbhum and appointed Srihari Pandey, deputy commissioner of Kolkata Armed Police, 3rd Battalion, as the Diamond Harbour police superintendent.
Banerjee alleged that the EC transfer orders came soon after Prime Minister Narendra Modi and a BJP candidate said in a TV programme that law and order situation in West Bengal is bad.