The invention discloses a novel household environment-friendly device, comprising a cooking fume collecting cover; a first fan is fixedly connected to the top of the cooking fume collecting cover, the top of the first fan is communicated with a smoke inlet pipeline, the right side of the smoke inlet pipeline is fixedly connected to a cooking fume collecting water tank body, the top of the cooking fume collecting water tank body is communicated with a gas pipe, the right side of the cooking fume collecting water tank body is fixedly connected to a microorganism clarifying tank, the microorganism clarifying tank is communicated with the cooking fume collecting water tank body by the gas pipe, the top of the gas pipe is communicated with a gas outlet pipe, the right side of the gas outlet pipe is fixedly connected with a formaldehyde processor, the right side of the formaldehyde processor is fixedly connected with a PM2.5 filter by the gas outlet pipe, and the right side of the PM2.5 filter is fixedly connected to an air detector by the gas pipe. The novel household environment-friendly device solves the problems that a traditional environment-friendly device cannot totally solve the household gas contamination and is poor in environment-friendly effect by cooperation of the cooking fume collecting water tank body, the microorganism clarifying tank, the formaldehyde processor and the PM2.5 filter.