Citrus Reticulata ‘Zhang Shuensis’ peels were collected in three different time points from the same plant growing in China. The peel oils extracted by hydrodistillation were investigated by GC-MS to study the changeability of oil components and their contents. It could be seen that the monoterpenes content was increased while the oxygenated compounds amount was decreased with the delay of harvested time. A total of 32 compounds were identified representing 98.4%, 98.2%, 98.8%, respectively. The main compounds in oils were limonene (65.8%, 69.4%, and 72.5%), γ-terpinene (7.5%, 8.1%, and 8.4%), and linalool (11.0%, 4.1%, 3.9%). These oils could be classified as the chemotype of limonene/linalool or limonene.