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Three dehumidification methods, forced ventilation using air-to-air heat exchangers, mechanical refrigeration dehumidifiers, and finned tubing condenser with chilled water, were compared with conventional greenhouse dehumidification method by temperature based ventilation. The heat exchangers and mechanical dehumidifiers were set up and evaluated in a tomato production greenhouse located in Saskatchewan, Canada, while the chilled water finned tubing condenser was designed and tested in a closed environment chamber at University of Saskatchewan. The comparison was made based on the moisture removal index and the energy costs. The method with chilled water condenser is less competitive than the others mainly due to the highest energy cost. Dehumidification by heat exchangers and dehumidifiers are more competitive than traditional forced ventilation in cold and mild seasons, but with warm weather conditions, the heat exchangers are less effective and both heat exchangers and dehumidifiers release heat to the greenhouse, which is undesirable. The method with dehumidifiers is the most promising because of the least energy consumption and its effectiveness all year round. Determining moisture removal requirement is the key for successful dehumidification for greenhouses.