The invention discloses a preparation method of low-sugar preserved fruits of cherry tomatoes. According to the preparation method, the cherry tomatoes are used as raw materials for preparing the low-sugar preserved fruits, and the optimal process conditions are as follows: performing color protection by using 0.1% of NaHSO3, 0.1% of Vc, 0.1% of citric acid and 0.1% of CaCl2 for 1h; blanching for 1min at the temperature of 98 DEG C; hardening by adopting 3% of delta-gluconolactone and 0.1% of calcium chloride for 4h; performing sugar infusion by using 35% of sugar liquid, 15% of dextrin and 0.3% of sodium carboxymethylcellulose for 30min under the vacuum condition that the vacuum degree is 0.07MPa; performing sugar boiling by using 50% of sugar liquid at the temperature being below 80 DEG C for 1h, wherein the temperature is lower than 80 DEG C; and drying with hot air for 17h. The results prove that by synthesizing three major indexes, namely sugar content, appearance and guarantee period, the low-sugar preserved fruits of the cherry tomatoes are better than those reported in literature and are basically in line with the requirements of the low-sugar preserved fruits.