Goole-based firm Croda PLC, Associated British Ports (ABP) Hull and Goole and Tryton Food Ltd have all been named the in Business In The Community's 2008 Yorkshire And Humber Environment Index.
East Riding Council and the University of Hull also feature in the list, which commends organisations for fulfilling their environmental goals.
The index is produced by Business In The Community – a body containing more than 800 of the UK's top firms that are committed to creating a positive impact on society.
It is based on responses to an environmental management questionnaire, which scores companies in relation to the goals they have achieved.
The average score on the index is 64 per cent, but Croda, ABP and Tryton all scored in the 80 to 89 per cent range.
Croda International also scored highly in the national index due, in part, to initiatives the company has implemented at its plant in Oak Road, north Hull.
Over the past seven years, the site has seen a 52 per cent decrease in gas and electricity used per ton of product manufactured, leading to a corresponding reduction in carbon emissions.
At the same time, water use per ton of product manufactured has reduced by 61 per cent.
The company is now continuing its green drive by erecting a two-megawatt wind turbine at its Oak Road site.
Electricity produced by the turbine will feed directly into the company's supply and will constitute more than a quarter of the factory's electricity requirement.