This paper studies the impact of low-carbon certification in a market with green consumers when the information of carbon emissions is asymmetric. The study explicitly models the negative utility of carbon emissions in the conventional utility function, and derives the demand function under different certification scenarios, and then optimizes the pricing decision. The conditions for getting certification are also specified. We compare the price, quantity sold, profit and expected emissions in the three scenarios:no certification, qualification-based certification and precise carbon footprint certification. The results show that low-carbon certification can effectively convey the information of emission levels, thus increase the consumers' surplus and the firm's profit. If the certification has enough influence and coverage, then the expected carbon emissions may decrease in the strong certification scenario. The qualification-based low-carbon certification is more adaptive. The certification granting organizations should set a less restrictive emission standard within the participation constraint for the objective to reduce expected carbon emissions.