This study was carried out on the hybrid F₁ "Katalina 522" which belongs to cherry tomato (Solanum lycopersicum var. cerasiforme) during the two seasons of 2018-2019 and 2019-2020 at a farm located in Zawyet Razeen village, Menoufia Governorate. The first step began with the labeling of flowers on the clusters starting at the full bloom to have nine fruit ages, namely 5, 10, 15, 20, 25, 30, 35, 40 and 45 days which were used to study the changes that occurred in the fruit physical and chemical characteristics in the collected developmental stages during cold storage to determine the maturity stage and the most suitable age for harvesting. The exerted figures showed that there was a rapid increase in the initial periods of the fruit fresh weight, size and diameter until the age of 20 days which was followed by a slow increase up to the age of 45 days, exhibiting statistically a curvilinear shape meanwhile the fruit firmness increased steadily till the age of 20 days after which a steady stable decline occurred till the last tested age of 45 days establishing in statistics a parabola shape. Moreover, the resulted data revealed a continuous quick gradual increase in T.S.S. and dry weight contents with the progress of age from the start of fruit formation up to the last examined age of 45 days that draw statistically a linear curve. However, the accumulation in the contents of ascorbic acid, lycopene and total sugars were increased gradually up to the age of 30 days, then followed by rapid increments up to the last age showing statistically a curvilinear shape. From another point of view, the characteristic of the pH reflects a gradual slow decrease with the progress of fruit age up to the age of 25 days followed by a steady gradual increase till the last age of 45 days. Storing these fruit developmental stages at 10ºC and 95% RH showed that the age of 35 days reflected the minimum loss in weight and the smallest unmarketable percentage during storage and at the same time contained the highest contents of T.S.S, ascorbic acid, lycopene, total sugars and dry weight. So, it is easy to show that the fruit maturity stage was attained at the age of 35 days, and the proper suitable age for harvesting was reached after 40 days.