The present paper studies the problem of Diophantine equation \(a^{x} + \left( {kb + 1} \right)^{y} = z^{2}\) , where \(a,b,k\) are positive integers, \(x,y,z\) are non-negative integers, \(a, \left( {kb + 1} \right)\) are primes such that \(a \equiv 1\left( {mod 3} \right)\) , and \(k\) is the multiple of 3. Results depict that there do not exist positive integers \(a,b,k\) , and non-negative integers \(x,y,z\) that satisfy the equation \(a^{x} + \left( {kb + 1} \right)^{y} = z^{2}\) .