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Focusing on the problem of fragmentation of plastic film and difficult recovery using machine, combining with the flexible features of corn seedlings, a plastic film collector which could recover plastic film during corn seedling period was designed. The plastic film was picked up by using pickup wheels which had inclined fingers, and separated from the wheels by using flat belt and sent to collecting box by using sweeping wheel. The key structural parameters were determined by mechanism analysis and tests. The main factors which influenced picking up of plastic film were inclined angle θ and length l of the inclined fingers. The picking up rate was no less than 95% and passing ability of the collector was good when θ=20° and l=40mm. Experiment results showed that the recovery rate was 92.1% and the injury rate to corn seedlings was less than 7.2% when the height of corn seedlings was lower than 30cm. The collector could fulfill to pick up plastic film during corn seedling period.