The reshuffle appears to have been prompted by the imminent ending of the moratorium on takeovers of ITV companies and the growing prospect that big television groups like Carlton may be allowed to swallow their smaller brethren.
HTV, left with hefty debts after bidding a very high price for its franchise, is widely perceived as among the most vulnerable takeover targets when the moratorium finishes at the end of this year.
Louis Sherwood, chairman, said: 'We are clearly on the threshold of a new era for ITV, and it's appropriate that a younger team should take the helm at this stage.'
Mr Rowlands was 'exactly the right man for the job'. He had successfully overseen the radical restructuring of HTV and introduced effective cost-control measures.
But Mr Sherwood did not think further significant rationalisations would be necessary. 'The debt level is coming down and we are currently running profitably,' he observed.
Mr Romaine, who will be 57 later this year, will receive some compensation for loss of office though the company refused to say how much. Under the HTV pension scheme, retirement is possible from the age of 57.
Last year Mr Romaine received pounds 65,440 in compensation, pounds 20,969 in removal costs, and pounds 32,275 of loan interest costs, on top of his pounds 125,458 salary, in respect of his relocation from Wokingham to Bristol after he was appointed chief executive but found he was unable to sell his home.
His disappearance marks the end of an era for HTV. Mr Sherwood and Mr Rowlands have backgrounds outside television and joined following the decision to shift the industry on to a system of competitive bidding for its franchises.
Mr Rowlands, 41, is a Cambridge economics graduate who joined HTV in May 1992 from the Asda retailing group, where he was deputy managing director of its property division.
Mr Sherwood, 52, became chairman in March 1991 after a career in retailing, latterly with the Gateway food markets chain.
The shares rose 1p to 56p.