Litterfall refers to the process by which leaves and other organic materials from the tree canopy fall to the ground, decompose and contribute nutrients to the soil. Plant litters are variable within and amongst forest ecosystems, and litter quality and decomposition affect the functioning of the forest, its productivity and plant growth. It is of ecological relevance to understand the major factors that determine litter production and decomposition in forest ecosystems, which helps provide information necessary for rehabilitation and sustainable forest ecosystem management in general. This study aimed to quantify Pinus halepensis litterfall and litter decomposition within the semiarid regions of Tebessa (Bekkaria and Gouraye) and the sub-humid region of Souk Ahras (Gouraye) in northeastern Algeria. Litterfall compounds were measured seasonally, annually, and after two years. During the same seasonal pattern, sub-humid stands receive more litterfall than other stands. Compared to the previous year, litterfall levels rose by 16.20% in Zaarouria and by 20.67% in Bekkaria. Autumn and winter account for the most litterfall due to the highest needle fall. After 1 and 2 years, the percentage of fragments and miscellaneous components in the litter had significantly increased. After 2 years, these processes occurred more frequently the amounts of litterfall collected at Zaarouria, Gouraye, and Bekkaria were respectively 3 to 2.6 and 2.4 times less than their corresponding seasonal and annual yields. Litterfall in sub-humid regions consists of more abundant fragments and miscellaneous items than in semi arid areas. In sub-humid regions, warmer temperatures and increased moisture levels speed up fragmentation and decomposition processes. These results suggest that high moisture content is the major cause of organic matter decomposition. Temperature is also important, which leads to a very close relationship, and the right balance between them provides a better decomposition. This study can help in afforestation projects as well as monitoring nutrient recycling and rehabilitation of forest ecosystems.