Let \(\pi (x;\gamma _1,\gamma _2)\) denote the number of primes p with \(p\leqslant x\) and \(p=\lfloor n^{1/\gamma _1}_1\rfloor =\lfloor n^{1/\gamma _2}_2\rfloor \) , where \(\lfloor t\rfloor \) denotes the integer part of \(t\in \mathbb {R}\) and \(1/2<\gamma _2<\gamma _1<1\) are fixed constants. In this paper, we show that \(\pi (x;\gamma _1,\gamma _2)\) holds an asymptotic formula for \(21/11<\gamma _1+\gamma _2<2\) , which constitutes an improvement upon the previous result of Baker (Mathematika 60(2):347–362, 2014).