Disposal of agricultural waste such as rice straw, as well as weed control are among the most common problems faced Egyptian farmers. Where using the chemical control of weeds and the burning of rice straw cause serious damage to the environment. This study was achieved on tomato crop because of considering one of the most important vegetable crops in Egypt and the most sensitive to the growth of weeds that is essential breadwinner of the white fly, which publishes serious viral diseases of the crop. The main objectives of this study were to search the effect of    adding rice straw pieces while cultivating operation. To obtain this aim manufacture  of cultivator consists of  two units, the first one (front four shares, two protector disks), the second adding rice straw pieces unit (hopper, feeding drum, directing tube and press wheel). Where the rice straw is biodegradable material, Cover rice straw pieces as mulches on ridge bottom avoiding tomato rows and the improving the profile of ridge bottom are a suitable choice for sustainable agriculture because they improve weed control and tomato crop performance. Also to investigate weed control and improving by using rice straw pieces cover. The rice straw pieces were the effective cover crop for suppressing weeds. After preparing the rice straw to suitable pieces aboveground biomass was placed in strips as dead mulch into which the tomato was transplanted in one row. Weed density and total weed aboveground biomass were assessed after15 and 30 days from tomato transplanting to evaluate the effect of cultivating with adding of rice straw pieces on weed control. The adding of rice straw pieces suppressed weeds in density and aboveground biomass compared to the conventional system. to evaluate the proto type manufactured cultivator, The equipment was tested under different operating conditions, at lengths of rice straw pieces (1.8, 2.5, 3.7 and 4.1 cm) rotor speed (63.7, 75.4, and 84.1 rpm) and three depths of press wheel (2, 3 and 4 cm). The results showed that the optimum length of rice straw pieces of 1.8 cm,  rotor speed 84.1 rpm and depth of cultivating  press wheel was 4.1 cm respectively due to its ability to level soil loosening, weed control, and ridge forming between rows and reconsolidate the soil led to improving of tomato crop yield.