The work aims to improve the acceptance of noni (Morinda citrifolia L.) juice with lemon juice, so as to provide a special flavor beverage for consumers. Orthogonal experimental optimization was used to obtain the optimum formula, gas chromatography-mass spectrometry (GC-MS) was adopted to explore the transformation of the aroma component, and electronic tongue was applied to detect the taste change. The optimum formula obtained by orthogonal experimental optimization was lemon juice of 15%, sucrose of 9%, and compound acid of 0.3% and the sensory evaluation value was 96.58. According to the aroma component analysis by GC-MS, the aroma component species of the compound juice with lemon rose to 44 from 20. The terpene species increased significantly, from 8 to 24, with relative amount increasing from 9.65% to 61.86%. The alcohol species increased from 4 to 10, with relative amount increasing from 19.01% to 31.12%. The main aroma components of the compound juice were D-Limonene (34.03%), 3-Carene (10.37%) and 3-Cyclohexene-1-methanol (18.34%), which had active role in the aroma formation of the compound juice. The relative amount of the octanoic acid as the main source of the bad smell reduced from 53.52% to 0.65%. From the results of electronic tongue, the compound juice sweetness rose to 8.57 from −3.21 and the acidity increased to 12.45 from 2.14. The taste of noni juice was improved after compounding. Lemon can increase the aroma substance species, cover up the foul smell of the octanoic acid, and improve the taste of the compound juice. This research provides the credible theoretical foundation for application of noni juice in the food industry.