The invention discloses an acid pickling method of a hot-rolled titanium roll. The method comprises the following steps that a, the hot-rolled titanium roll to be subject to acid pickling is subject to continuous annealing treatment, and then shot blasting treatment is carried out; b, clean water is used for carrying out pre-cleaning on the hot-rolled titanium roll subject to shot blasting treatment, and after cleaning, a brush roller is used for brushing; c, the brushed hot-rolled titanium roll is fed into an acid tank to be subject to acid pickling, a pickling solution is an HNO3 and HF mixed solution, and in the acid pickling process, HF is replenished into the acid tank in time; and d, the hot-rolled titanium roll obtained after acid pickling is brushed and washed through clean water, and finally drying is achieved. Before being subject to acid pickling treatment, the hot-rolled titanium roll is subject to shot blasting treatment, the oxide layer on the surface of the hot-rolled titanium roll is broken, the pickling solution can make sufficient contact with the oxide layer, the pickling efficiency of the oxide layer is improved, due to the fact that the pickling solution can have the sufficient reaction with the oxide layer, the use amount of the pickling solution can be reduced, and acid stains formed on the surface of the titanium roll due to the fact that excessive amount of pickling solution is used are avoided.