The invention discloses a method and device for inspecting fatty acid as well as a terminal. The method comprises the following steps of: acquiring sample parameters of a sample to be detected selected by a user; providing a plurality of to-be-detected fatty acid items of the sample to be detected to the user; receiving a target fatty acid item which is selected from the plurality of to-be-detected fatty acid items by the user; and calculating the content of the target fatty acid item in the sample to be detected according to the sample parameters and the target fatty acid item. According to the method disclosed by the invention, the content of the target fatty acid item in the sample to be detected is directly calculated according to the sample parameters; in a calculation process, needed parameters do not need to be manually input by the user, so that the condition that a calculation result is not accurate, caused by manual incorrect operation, is reduced, the accuracy and reliability of the calculation result are improved, and the calculation efficiency is improved.