His dismissal, which takes effect immediately, was unveiled by caretaker Transport Minister Chadchart Sittipunt on Thursday.
Chamroon Tangpaisalkit, the SRT Electric Train board chairman, said the decision to give him his marching orders was made in a meeting on Wednesday after an investigating committee concluded he be dismissed for using fake papers to apply for the post.
The probe began after the company received a complaint in July last year.
One of the requirements for the position is experience in an executive position of any firm with at least a billion baht turnover.
Investigators contacted the firm cited by Mr Peerakan in his papers used to apply for the top job of the SRT Electric Train. The company denied any connection, according to the board chairman. It had turnover of only 400 million baht, he added, without naming the company.
Mr Peerakan could not clarify matters and countered the investigation with his own evidence, Mr Chamroon said.
He could face civil and criminal suits, including the refunding of his monthly salary of 120,000 baht to the company. The issue will be tabled in the next board meeting, Mr Chamroon said.
ACM Khamrop Leeyawanich is acting managing director.
Mr Peerakan refused to acknowledge the board decision to part ways with him, but all officials had been informed of it, the board chairman said.
Mr Peerakan was the first managing director of the firm after signing a contract in May last year.
SRT Electric Train has to inform its parent firm, the State Railway of Thailand (SRT), for approval to seek a replacement, SRT governor Prapas Chongsanguan said.