In the present paper, we introduce some new families of elliptic curves with positive rank arising from Pythagorean triples. We study elliptic curves of the form y 2 = x 3 − A 2 x + B 2 , where A, B ∈ {a, b, c} are two different numbers and (a, b, c) is a rational Pythagorean triple. First of all, we prove that if (a, b, c) is a primitive Pythagorean triple (PPT), then the rank of each family is positive. Furthermore, we construct subfamilies of rank at least 3 in each family but one with rank at least 2, and obtain elliptic curves of high rank in each family. Finally, we consider two other new families of elliptic curves of the forms y 2 = x(x − a 2 )(x + c 2 ) and y 2 = x(x − b 2 )(x + c 2 ), and prove that if (a, b, c) is a PPT, then the rank of each family is positive.