In the application of vacuum optical tweezers, a dipole trap formed by laser light with a spatial gradient is usually used to trap neutral atoms or micro/nano particles. In the experiment of optical trapping neutral atoms, dipole trap with laser frequency far detuned from the atomic transition is usually adopted in order to suppress the photon scattering rate from the trapped atom. The storage time of the optically trapped atoms is mainly affected by the intensity noise and the pointing noise associated with the dipole field. The storage time is far less than the value determined by the background vapor pressure. In order to prolong the storage time as well as the decoherence time of the trapped particles, we invent a method to use a single-stage feedback loop based on an electro-optical amplitude modulator (EOAM) to suppress the low-frequency intensity noise associated with a 1 064 nm laser beam. The intensity noise from 0 Hz to 1 MHz can be effectively suppressed with a reduction up to 20 dB below 100 kHz and 10 dB below 500 kHz. The standard deviation of optical power fluctuation has decreased to 0.5%, which is an order of magnitude improvement. The noise-suppressing range covers the typical parametric heating frequencies of the optical dipole trap. Therefore, it can be used to improve the trapping performance of these particles, such as the storage time of particles and the coherence time of quantum states. By applying the setup to our single cesium atom experiment, the atomic heating rate is reduced by two orders of magnitude. Thus, we can extend the storage time of a single atom by two orders of magnitude. The measured decoherence time is also enhanced five times. The setup is simple and flexible, so it can be easily applied to the optical trapping of a neutral atom or nano/micron particles with a laser with all kinds of wavelengths.