A field  experiment was conducted on tomato plants, hybrid (010)  at Ibshway, Fayoum governorate, Egypt in  winter season (2014-2015).  Three replicates were used to study the interaction effects of different organic manures [(compost, chicken manure and femnyard manure, and three potassium levels (K₀, K₁, K₂ liquid potassium 38%)] on the biodiversity of mites and the yield of tomato. Random samples of debris, litters and soil are collected every ten days intervals from November 2014 to January 2015. The results revealed 33 species of 27 genera in 21  families from A stigmata, Prostigmata, Mesostigmata and Cryptostigmata. Famiy Scutacaridae ranked the first in populations followed by Family Haplozetidae. The effect of three levels or organic fertilizers was recorded.  The interaction  effects between organic manures  and potassium levels on tomato yield also were discussed.